Harlequinmania

Click through to see the images. Last night, Marc Levenson of Reef Addicts announced that Jaques Cousteau's son Jean-Michel will present the keynote address at the Saturday Night Gala of the Dallas/Fort Worth MACNA event this September. This is certainly a treat for everyone attending and Jean-Michel's presence at the event is in large part due to Seachem. Jean-Michel has continued his father's legacy and has produced over 70 films, received the Emmy, the Peabody Award, the 7 d’Or, and the Cable Ace Award. He is also a syndicated Los Angeles Times columnist where his column reaches over 60 countries. In addition he is the founder of the Ocean Futures Society that explores the world's oceans and educates the public on its protection. We urge everyone that plans to attend MACNA this year to get your tickets now for the Gala as tickets are only $129 until June 30. This will be a gala that you do not want to miss! View the full article

Click through to see the images. About Flashback Fridays: Every Friday, Advanced Aquarist will repost a blog article from this week one year ago. With all the content we publish, we want to share the timeless and interesting articles for our new readers as well as regulars who may have missed the original blog article. In January 2011, The Steinhart Aquarium in the California Academy of Sciences received a Caribbean Octopus 'vulgaris' for display. It quickly took up residence inside a glass bottle, which is exactly what I wanted it to do so it would always be visible to guests. Just as quickly, it moved back under some rock and started denning, and my heart sank because we knew it was a she, and the she had laid eggs. While eggs being laid in captivity is generally an exciting event, this particular species, like many but not all octopus, stops eating after it lays eggs and dies soon after they hatch which tends to put a damper on joyous hooplah. Even worse, this species is 'small egged' meaning it produces large numbers of very small planktonic 'paralarvae' which are notoriously difficult to feed and raise. So, we tilted the rock where the eggs were laid to make them visible to the public (but in a high flow area so they would continue to develop), and the adult octopus moved back into the bottle making for an all round cool and educational display of something most people don't get to see. The unexpected icing on the cake was catching the hatching of the eggs from start to finish, and also being able to get much of it on video. Although we weren't able to raise the hatchlings to maturity, something few have done (if at all), we were able to keep them alive for 26 days, and the image of a waterfall of tiny octopus paralarve flowing up from the egg mass to the surface of the water is something I don’t think we will ever forget. http://vimeo.com/20288962 Nuts and bolts Caribbean Octopus 'vulgaris' (there are several Octopus that use the species name vulgaris which is why its in quotes) Roughly 3 weeks between eggs being laid and eggs hatching. Hatching occurred at 9 am. When I turned off the flow to better witness the hatching, the female octopus quickly left her bottle den, agitated the eggs presumably to help the hatch, and is now sadly protecting the space where the eggs were. The female many hatchlings will be on display at the Steinhart Aquarium in the California Academy of Sciences until they can no longer be displayed. The hatchlings are 1-2 mm in length. There are 1000's of them. The hatchings are in a Kreisel tank and being offered 24 hour Artemia, which the literature suggests is the correct size to be eaten by the little octos, along with rotifers which are smaller to cover all the bases we can reasonably cover. A previous batch of hatchlings from my home had individual paralarvae survive until day 9, some of these survived until day 26 The Caribbean Octopus 'vulgaris' seems to be a smaller species than its larger Mediterranean Octopus vulgaris cousins For more information on keeping and breeding cephalopods check out www.TOMNO.com. Some pics A very posed photo in a drop of water The lines in the upper corner are millimeters. The female in her bottle. Note she has plugged the opening with rubble. After I disturbed her den and eggs, she moved into the bottle and laid 4 or 5 additional strands of eggs in the bottle. View the full article

Forests in the Amazon Basin are expected to be less vulnerable to wildfires this year, according to the first forecast from a new fire severity model. View the full article

Click through to see the images. For those without access to Nat Geo TV, you're in luck. Nat Geo will upload full episodes of Fish Tank Kings after they air. The premiere episode will follow Living Color Aquariums as they build the Marlins Stadium backstop aquarium. Subsequent episodes will feature multiple builds and tours per show, including visits to Curacao, Florida Aquarium, Tennessee Aquarium, and ORA Farms! FTK has promised us an inaugural season full of entertainment and education. View the full article

The cone snails are predators of the sea. They capture fish by injecting a venom into the prey that consists of a cocktail of different substances. The single components of the snails' venom, so-called conopeptides, are known for their extraordinary pharmacological properties and potential. View the full article

The cone snails are predators of the sea. They capture fish by injecting a venom into the prey that consists of a cocktail of different substances. The single components of the snails' venom, so-called conopeptides, are known for their extraordinary pharmacological properties and potential. View the full article

Click through to see the images. New research focusing on tooth development in the deadly fish - unchanged through evolution - shows that after the first generation of teeth the programme for continued tooth replacement modifies to form a distinctive and unusual `parrot like´ beak. The study, which is the first time scientists have analysed the development of the fish´s unique beak, also supports the idea that evolution doesn´t make jumps, as its distinctive bite has been modified from a set of genes responsible for tooth development and preserved over 400 million years. Dr Gareth Fraser of the University of Sheffield´s Department of Animal and Plant Sciences, who led the project, said: "It goes beyond fishes and even morphological novelty; we can use the pufferfish beak as a model for a simplified tooth replacement system – composed of just four continually replacing teeth that make up the beak structure. It is of great interest for science to understand the process of tooth replacement, to understand the genes that govern the continued supply of teeth and mechanisms of dental stem cell maintenance. "As humans only replace their teeth once, fishes and pufferfish in particular, can be looked at as a new model to help us to answer questions like how continuous tooth replacement programmes are maintained throughout life? This would help our understanding of why humans have lost this replacement potential, and furthermore how can we use knowledge of the genetic underpinnings of tooth replacement in fishes to facilitate advances in dental therapies." Photo by Edward Callaghan Pufferfish are bony fish, which are extremely diverse and make up almost half of all living vertebrates. This group uses a highly conserved process to form a unique beak-like jaw that has made teeth in all vertebrates – animals with spines – for millions of years. The research catalogued the dental development throughout all stages of the pufferfish´s growth, from the production of initial-teeth to the construction of its distinctive `beak´. The research showed that the strange structure didn´t appear from scratch during embryonic development as a complete vertebrate novelty, but rather originates from the modified development of replacement teeth after the formation of an initial dentition, which appears like `normal´ fish teeth. Dr Fraser added: "The beak structure is made from many bands of dentine, stacked together, each band represents a new replacement `tooth´, and they can have more than seven separate bands making up the beak, with new bands continuously being formed to replace those damaged by eating. "Only after the start of the tooth replacement programme in just four of these first-generation teeth does this novel and bizarre beak-like structure appear. It is an example of re-specification of its genetic tool-kit for tooth development toward a very alternative, and unique, dentition. Pufferfishes are the most bizarre of the bony fishes and have recently become a useful genetic model with the pufferfish genome project near completion. It is hoped it will provide a valuable model system for genetics, genomics, biomedical sciences and now development, not to mention the importance of this group to our understanding of the evolution of morphological novelty and vertebrate diversity. The paper is published in the journal PNAS and was carried out in collaboration with the Natural History Museum, London and King´s College London. (press release via The University of Sheffield, photo via Red Sea Holidays) View the full article

Click through to see the images. The first aquarium is currently under construction at Greater Noida and is slated for completion by the end of 2012. The new aquarium is named The Blue Planet; If the name rings a bell, it's because several aquariums including the upcoming Danish masterpiece also goes by the same name. The Blue Planet at Greater Noida will be India's first state-of-the-art public aquarium. Andover does not plan to stop there and is exploring multiple sites to build at least six more public aquariums over the next five years. View the full article

Groupers, a family of fishes often found in coral reefs and prized for their quality of flesh, are facing critical threats to their survival. Scientists report that 20 species are at risk of extinction if current overfishing trends continue, and an additional 22 species are near "threatened" status. View the full article

Groupers, a family of fishes often found in coral reefs and prized for their quality of flesh, are facing critical threats to their survival. Scientists report that 20 species are at risk of extinction if current overfishing trends continue, and an additional 22 species are near "threatened" status. View the full article

Researchers have developed a new technique which allows them to measure brain activity in large populations of nerve cells at the resolution of individual cells. The technique has been developed in zebrafish to represent a simplified model of how brain regions work together to flexibly control behavior. View the full article

The Encyclopedia of Life has surged past one million pages of content with the addition of hundreds of thousands of new images and specimen data. Launched in 2007 with the support of leading scientific organizations around the world, the Encyclopedia of Life provides global access to knowledge about life on Earth by building a web page for each of the 1.9 million recognized species. View the full article

The Encyclopedia of Life has surged past one million pages of content with the addition of hundreds of thousands of new images and specimen data. Launched in 2007 with the support of leading scientific organizations around the world, the Encyclopedia of Life provides global access to knowledge about life on Earth by building a web page for each of the 1.9 million recognized species. View the full article

Click through to see the images. Follow Matt Pedersen's progress with breeding the Lightning Maroon Clown on his The Lightning Project blog. A long-awaited congrats to Matt! We hope to witness the hatching of little "sparks." " height="360" style="width: 600px;" type="application/x-shockwave-flash" width="600"> "> "> View the full article

Click through to see the images. Follow Matt Pedersen's progress with breeding the Lightning Maroon Clown on his The Lightning Project blog. A long-awaited congrats to Matt! We hope to witness the hatching of little "sparks!" " height="360" style="width: 600px;" type="application/x-shockwave-flash" width="600"> "> "> View the full article

Scientists have found that genetic information on the Antarctic octopus supports studies indicating that the West Antarctic Ice Sheet could have collapsed during its history, possibly as recently as 200,000 years ago. View the full article

Click through to see the images. With the help of my colleague David Flanigan, an organic chemistry professor and fellow reef aquarist, I tested the effectiveness of some reflectors used with T-5 fluorescent bulbs in aquarium lighting fixtures. We knew that any sort of reflector in a fixture would help send more light downward into a tank, but we wanted to see some hard data, and wanted to compare a couple of different types of reflectors in the process. So, we set up a test tank, got a light meter and a couple of fixtures, and got to work. To start, we cut up and marked some eggcrate, attached it to a PVC frame we built (along with uprights of different lengths that could be switched out to take readings at different depths), and got a light meter. We went with the Apogee Instruments Quantum Meter with a cabled sensor, after reading Riddle (2005 & 2008) and talking to lighting expert Sanjay Joshi. This meter measures PAR (Photosynthetically Active Radiation), the important part of the spectrum for organisms that use light, which is also called PPFD (Photosynthetic Photon Flux Denisty). It does this, and then reports intensity in units called micro-Einsteins per square meter per second (µE·m²·sec) or micro-Mol per square meter per second (µMol·m²·sec). Riddle (2008) covers this in more detail, so give it a read if you like. There are numerous pre-fabricated T-5 fixtures available, and all that I've seen have some sort of reflector included. However, some fixtures have a single reflector that's typically a flat or curved sheet of polished aluminum mounted above all the bulbs in the fixture, while many others have a single, smaller aluminum reflector for each individual bulb. These tend to wrap around half of the bulb and have some number of bends/folds in the aluminum. So, we got one of each type of fixture and tested both. During our tests, we made some other discoveries, quite on accident, and I want to go over a couple of these first, though. The Background Effect While some aquarists might leave the back of their tank alone, or may cover it with a sheet of colored plastic, it's common practice to tape up the sides and top of a new tank and spray paint the back of it blue or black. However, one of the accidental discoveries we made was that this can significantly reduce the amount of light that is reflected into a tank. Our test tank was a 95 gallon tank with dimensions of 24" high x 18" wide x 48" long, as this is a popular footprint, and we did much of our testing with the tank full of water after we found that this can also make a significant difference in readings. The tank was also painted light blue on the backside. Like those of many hobbyists, our test tank had a painted blue background. When we started testing, we assumed that light readings would always be lower at the front of the tank and higher at the back. The reasoning was that some of the light from the bulbs should be reflected off the front pane of glass back into the tank and off the rear pane of glass into the tank - but that more light would "escape" through the clear front pane, while more would be reflected back in from the painted back pane. However, were wrong, as the readings at the front of the tank, without exception, were higher instead of lower than those at the back of the tank. To develop an understanding of why this happened, look at the lighting "footprint" below of our TX5 48" fixture that houses five 48" T-5 bulbs, which was generously donated by Aquactinics. The units are PAR (as µMol·m²·sec) measured in the tank with the sensor at 10" water depth, and note that the front of the tank is at the bottom of the figure. Average PAR at the front of the tank was calculated by adding the 11 readings taken at approximately 1" from the front pane of glass during each test and dividing that sum by the number of readings taken (11). Notice that the light intensity was lower at the back of the tank where the average was 167 µMol·m²·sec (top of the footprint), and higher at the front where the average was 234 µMol·m²·sec (bottom of the footprint). We found that the same thing happened when we later tested our Nova Extreme fixture that houses four 48" T-5 bulbs, our Orbit fixture that houses four 21" PowerCompact bulbs, and even our Outer Orbit fixture that houses four 48" T-5 bulbs and two 150w DE metal halide bulbs (all of which were generously donated by Current USA). For some reason the painted blue background, without exception, made the back of the tank darker than the front. It occurred to us that we could take a look at the effect a colored plastic background would have on readings. So, we tightly taped a blue plastic background to the front of the tank to see if the readings would then equal those at the back. The background material we had was about the same color blue as the paint on the back of the tank, so we thought that's what would happen. Wrong again. Let's look at the new footprint, again with the TX5 fixture and everything else the same except for the addition of the plastic sheet. Well, it looks the same. The readings were essentially the same as before, being ever so slightly higher at the front of the tank. Apparently it was something about the paint itself, rather having something blue on the front/back of the tank. So, just for the fun of it we tried a black plastic background. It didn't really change the readings, either. Thus, it seemed that the color of the plastic sheer didn't matter. The front was still brighter than the back. Then Dave had a great idea. Next, we tried the blue plastic background again, but this time we wetted the glass on the front of the tank, stuck the plastic to it and then pushed all the air bubbles out from underneath it. Basically our simulated painted background looked just like the real painted background, and was stuck onto the pane itself with no air in between the plastic and the glass. This time we got something totally different, as you can see on the new footprint. Oddly enough, the readings at the front mirrored those of the back of the tank. Note that the average PAR at the front of the tank is approximately 30% lower than it was when we started, and is essentially identical to the readings along the back (an average of 166.6 µMol·m²·sec for the back vs. 166.9 µMol·m²·sec for the front)! Okay, so we did one more. Next, we wetted the front of the tank and did the same thing with the black plastic background. The readings dropped even lower, as the average at the front was 155 µMol·m²·sec. So, the front of the tank, with its simulated painted black background, was noticeably darker than the back of the tank with its painted blue background. In fact, the average PAR was down approximately 34%. Again, this was not what we expected at all. So, we tracked down physics professor Brain Lane, looking for a possible explanation. As he explained, in simple terms, when light leaves its source and hits the panes of glass in the tank, some of that light escapes through the glass, but some is reflected off the inner surface of the glass and heads back into the tank. As strange as it might sound, some of the light also reflects off the inner "surface" of the outer side of the glass pane, too (see the figure below). However, apparently having something "sealed" against the glass, such as blue paint or a wetted blue plastic background stops some of the light from reflecting off the inner surface of the outer side of the glass pane. If anything else was going on, taping the dry plastic background on the tank would have the same effect - but it didn't. Some light bounces off the inner surface of the glass back into a tank, and some also bounces off the inner surface of the outer side of the glass pane. Yes, that sounds odd, but you can easily see some of the weird reflections created when mixing glass, air, and water. Have you ever noticed that if you look right through the front of the tank it looks clear, but if you look through the end of your tank the front pane of glass looks like a mirror? Take a look now if you've never noticed this before. Of course, this doesn't happen if there's no water in the tank, as you can see right through the front pane, even when looking at it through the end of the tank. Anyway, at this point I want to make some basic recommendations related to the topic. 1) If you have a wall of live rock from the bottom almost to the top of your tank, then don't worry about the background too much. Most of the reflection takes place several inches from the top of the tank. 2) If you have considerable areas of glass exposed at the back of the tank, unobstructed by rocks, use a taped on plastic background instead of paint. Or, try putting your tank close to a wall and just paint the wall behind it blue/black. Again, this can result in the back of the tank being as much as 30% brighter than if it was painted. 3) Always keep your glass clean to promote better reflection regardless of backgrounds, which includes scraping away coralline algae. 4) Don't paint the front of your tank For a different look, I put nothing on the back of this 55 gallon tank and just painted the wall behind it blue. The Temperature Effect In addition to the background effect, we also noticed another pattern in the numbers that persisted regardless of the type of fixture. The readings were always lower at one end of any given fixture than at the other end, and if you scroll back up and look at the footprints above, you'll see this. The readings were always a little higher on the left end of the TX5 fixture, and we found that this caused by a difference in bulb temperature from one end to the other. I'll go into more detail on this in a future article, but for now it's enough to point out that the 3" exhaust fan in the fixture was on the right end and it drew relatively cool air from the room into the left end. As the air passed over the bulbs it became increasingly hotter, meaning the bulbs were slightly cooler at the left end of the fixture. Every bulb has an optimal operating temperature, and in this case the bulbs' output fell off a little at the right end of the fixture due to the increase in temperature. While the end to end differences weren't drastic by any means, they were consistently there. It's unlikely that anyone will be cutting holes in a pre-fabricated fixture and/or upgrading the included fans, but if you decide to install a lighting retro-fit kit into a canopy, be sure to use an appropriately-sized fan(s) for the job and give some thought to placing it/them in the top-center of the canopy with vents in both ends. Putting the fan in the top-center and vents in the ends would decrease the distance that room-temperature air travels over the bulbs, and would keep both ends of the bulbs at approximately the same temperature. Test Results for a Fixture with a Single Reflector Okay, let's get on to how we tested some T-5 bulbs with a single sheet-type reflector that has a single fold down each edge, and what we found. To start, we grabbed our Nova Extreme fixture that houses four 48" T-5 bulbs and includes a single polished aluminum sheet mounted above bulbs. Then, we covered the entire reflector with black electrical tape. We put the bulbs in, set the fixture up over our testing rack, and fired it up. One little thing to note here is that we waited about half an hour to start taking readings, as we found that it takes a while for systems to warm up and the light output to stabilize. Again, output changes depending on bulb temperature. After everything was ready, we took a series of readings to measure PAR using our meter. Readings were taken at fifteen positions under the fixture, five from end to end and three across (see the grid on the figures below). Note that the bottom of the fixture was approximately 5.25" inches from the top of the light meter's sensor. After finishing that up, we pulled out the black tape, got the fixture warmed up again, and took the same series of readings. This let us make a direct comparison between the light that would be going down into a tank with and without the reflector. With the reflector blacked-out the highest PAR reading we got was 191 µMol·m²·sec. We also found that the average PAR was 155 µMol·m²·sec, which was calculated by adding all the readings together and dividing the sum by 15. With the tape pulled off the reflector the highest PAR reading was 435 µMol·m²·sec, and the average PAR was 342 µMol·m²·sec. That's quite a difference to say the least, as the average PAR went from 155 to 342 µMol·m²·sec! So, it should be quite clear that the use of a sheet-type reflector can make a heck of a difference in the amount of light going from a T-5 bulb to the critters in your tank. Test Results for a Fixture with Individual Reflectors Next, we tested our TX5 48" fixture that houses five 48" T-5 bulbs with individual reflectors for each bulb. They're the type that has numerous folds, and have a little ridge that runs right down the middle of the reflector, too. This little ridge is supposed to angle away the light going straight up from the bulb, rather than reflecting it straight back down into the bulb. Again, these reflectors wrap around each bulb to some degree, and we expected them to be even better than the single sheet-type reflector. Note that due to the width of the fixture we decided to use only three bulbs in it, so the readings we got were lower than those presented above. This doesn't really matter though, as we were looking for the change in readings with and without reflectors rather than the total output of a given fixture. Again, we covered each of the reflectors with black electrical tape, put the bulbs in afterwards, set the fixture up over our testing rack, and warmed it up. We took a series of readings in the same manner, and then pulled out the black tape, got the fixture warmed up again, and took the same series of readings once again. With the reflectors blacked-out the highest PAR reading was 128 µMol·m²·sec, and the average PAR was 101 µMol·m²·sec, which again was calculated by adding all the readings together and dividing the sum by 15. With the tape removed the highest PAR reading was 451 µMol·m²·sec, and the average PAR was 304 µMol·m²·sec. So, we were right to think these would send even more light downwards, as the average PAR went from 101 to 304 µMol·m²·sec! Thus, again, it should be obvious that the use of well-designed reflectors, individual-types in this case, can make a huge difference in the amount of light going from a T-5 bulb down into a tank. Other Bulbs So, what about V.H.O. bulbs? Do reflectors make as big a difference? Well, all of the V.H.O. bulbs I've ever used had an internal reflector. I assume that's because they have a larger diameter making it easier to add some sort of coating to half of the inside of the bulb to send all the light in one direction. However, we didn't do any sorts of tests on V.H.O.s and I've never broken one open to see what's in there, so I'm not positive about that. Regardless, I don't know of anyone that makes individual reflectors for V.H.O. bulbs. Maybe we'll try a sheet-type reflector with some in the future though, just to see if there's any difference. Likewise, the bulbs used in the L.E.D. fixtures I've seen always come mounted in little individual reflectors, so we didn't test any L.E.D.s without reflectors, either. Metal halide bulbs and the reflectors made for them come in a range of shapes and sizes and finishes, but there's already a good bit of information about these available. Sanjay Joshi has looked at many of them and written up the results in a series of articles (see references below), but what I'll tell you here is that the right reflector can make a huge difference, and the wrong one won't help much. So, if you're thinking about retro-fitting some into a canopy, I recommend you do some homework on bulb/reflector combinations. Bottom Line It is imperative that you use reflectors with T-5 bulbs, and individual reflectors do a better job of sending light into a tank than a single reflector. If for some reason you decided to add some T-5s to a canopy yourself, the data show that you'd need three bulbs without reflectors to send the same amount of light into the tank as one bulb with a quality individual reflector! Also, don't paint the back of your tank, and make sure that your bulbs are adequately cooled for optimal performance. References / Sources for More Information Joshi, S. and Marks, T. 2003. Analyzing Reflectors: Part I - Mogul Reflectors. Advanced Aquarist's Online Magazine: 2(3). Joshi, S. and Marks, T. 2003. Analyzing Reflectors: Part II - Double Ended Lamp Reflectors. Advanced Aquarist's Online Magazine: 2(7). Joshi, S. and Marks, T. 2004. Analyzing Reflectors: Part III. Advanced Aquarist's Online Magazine: 3(3). Joshi, S. and Marks, T. 2004. Analyzing Reflectors: 400w DE Reflectors. Advanced Aquarist's Online Magazine: 3(12). Joshi, S. and Marks, T. 2006. Analyzing Reflectors: Part V. Advanced Aquarist's Online Magazine: 5(2). Joshi, S. 2006. Facts of Light Part I: What is Light? Reefkeeping: 5(1). Joshi, S. 2006. Facts of Light Part II: Photons. Reefkeeping: 5(2). Joshi, S. 2006. Facts of Light Part III: Making Sense of Light Measures. Reefkeeping: 5(3). Riddle, D. 2005. Product Review: A Comparison of Two Quantum Meters - Li-Cor v. Apogee. Advanced Aquarist's Online Magazine: 4(7). Riddle, D. 2008. Product Review: Lighting for Reef Aquaria: Tips on Taking Light Measurements. Advanced Aquarist's Online Magazine: 7(2). View the full article

Click through to see the images. With the help of my colleague David Flanigan, an organic chemistry professor and fellow reef aquarist, I tested the effectiveness of some reflectors used with T-5 fluorescent bulbs in aquarium lighting fixtures. We knew that any sort of reflector in a fixture would help send more light downward into a tank, but we wanted to see some hard data, and wanted to compare a couple of different types of reflectors in the process. So, we set up a test tank, got a light meter and a couple of fixtures, and got to work. To start, we cut up and marked some eggcrate, attached it to a PVC frame we built (along with uprights of different lengths that could be switched out to take readings at different depths), and got a light meter. We went with the Apogee Instruments Quantum Meter with a cabled sensor, after reading Riddle (2005 & 2008) and talking to lighting expert Sanjay Joshi. This meter measures PAR (Photosynthetically Active Radiation), the important part of the spectrum for organisms that use light, which is also called PPFD (Photosynthetic Photon Flux Denisty). It does this, and then reports intensity in units called micro-Einsteins per square meter per second (µE·m²·sec) or micro-Mol per square meter per second (µMol·m²·sec). Riddle (2008) covers this in more detail, so give it a read if you like. There are numerous pre-fabricated T-5 fixtures available, and all that I've seen have some sort of reflector included. However, some fixtures have a single reflector that's typically a flat or curved sheet of polished aluminum mounted above all the bulbs in the fixture, while many others have a single, smaller aluminum reflector for each individual bulb. These tend to wrap around half of the bulb and have some number of bends/folds in the aluminum. So, we got one of each type of fixture and tested both. During our tests, we made some other discoveries, quite on accident, and I want to go over a couple of these first, though. The Background Effect While some aquarists might leave the back of their tank alone, or may cover it with a sheet of colored plastic, it's common practice to tape up the sides and top of a new tank and spray paint the back of it blue or black. However, one of the accidental discoveries we made was that this can significantly reduce the amount of light that is reflected into a tank. Our test tank was a 95 gallon tank with dimensions of 24" high x 18" wide x 48" long, as this is a popular footprint, and we did much of our testing with the tank full of water after we found that this can also make a significant difference in readings. The tank was also painted light blue on the backside. Like those of many hobbyists, our test tank had a painted blue background. When we started testing, we assumed that light readings would always be lower at the front of the tank and higher at the back. The reasoning was that some of the light from the bulbs should be reflected off the front pane of glass back into the tank and off the rear pane of glass into the tank - but that more light would "escape" through the clear front pane, while more would be reflected back in from the painted back pane. However, were wrong, as the readings at the front of the tank, without exception, were higher instead of lower than those at the back of the tank. To develop an understanding of why this happened, look at the lighting "footprint" below of our TX5 48" fixture that houses five 48" T-5 bulbs, which was generously donated by Aquactinics. The units are PAR (as µMol·m²·sec) measured in the tank with the sensor at 10" water depth, and note that the front of the tank is at the bottom of the figure. Average PAR at the front of the tank was calculated by adding the 11 readings taken at approximately 1" from the front pane of glass during each test and dividing that sum by the number of readings taken (11). Notice that the light intensity was lower at the back of the tank where the average was 167 µMol·m²·sec (top of the footprint), and higher at the front where the average was 234 µMol·m²·sec (bottom of the footprint). We found that the same thing happened when we later tested our Nova Extreme fixture that houses four 48" T-5 bulbs, our Orbit fixture that houses four 21" PowerCompact bulbs, and even our Outer Orbit fixture that houses four 48" T-5 bulbs and two 150w DE metal halide bulbs (all of which were generously donated by Current USA). For some reason the painted blue background, without exception, made the back of the tank darker than the front. It occurred to us that we could take a look at the effect a colored plastic background would have on readings. So, we tightly taped a blue plastic background to the front of the tank to see if the readings would then equal those at the back. The background material we had was about the same color blue as the paint on the back of the tank, so we thought that's what would happen. Wrong again. Let's look at the new footprint, again with the TX5 fixture and everything else the same except for the addition of the plastic sheet. Well, it looks the same. The readings were essentially the same as before, being ever so slightly higher at the front of the tank. Apparently it was something about the paint itself, rather having something blue on the front/back of the tank. So, just for the fun of it we tried a black plastic background. It didn't really change the readings, either. Thus, it seemed that the color of the plastic sheer didn't matter. The front was still brighter than the back. Then Dave had a great idea. Next, we tried the blue plastic background again, but this time we wetted the glass on the front of the tank, stuck the plastic to it and then pushed all the air bubbles out from underneath it. Basically our simulated painted background looked just like the real painted background, and was stuck onto the pane itself with no air in between the plastic and the glass. This time we got something totally different, as you can see on the new footprint. Oddly enough, the readings at the front mirrored those of the back of the tank. Note that the average PAR at the front of the tank is approximately 30% lower than it was when we started, and is essentially identical to the readings along the back (an average of 166.6 µMol·m²·sec for the back vs. 166.9 µMol·m²·sec for the front)! Okay, so we did one more. Next, we wetted the front of the tank and did the same thing with the black plastic background. The readings dropped even lower, as the average at the front was 155 µMol·m²·sec. So, the front of the tank, with its simulated painted black background, was noticeably darker than the back of the tank with its painted blue background. In fact, the average PAR was down approximately 34%. Again, this was not what we expected at all. So, we tracked down physics professor Brain Lane, looking for a possible explanation. As he explained, in simple terms, when light leaves its source and hits the panes of glass in the tank, some of that light escapes through the glass, but some is reflected off the inner surface of the glass and heads back into the tank. As strange as it might sound, some of the light also reflects off the inner "surface" of the outer side of the glass pane, too (see the figure below). However, apparently having something "sealed" against the glass, such as blue paint or a wetted blue plastic background stops some of the light from reflecting off the inner surface of the outer side of the glass pane. If anything else was going on, taping the dry plastic background on the tank would have the same effect - but it didn't. Some light bounces off the inner surface of the glass back into a tank, and some also bounces off the inner surface of the outer side of the glass pane. Yes, that sounds odd, but you can easily see some of the weird reflections created when mixing glass, air, and water. Have you ever noticed that if you look right through the front of the tank it looks clear, but if you look through the end of your tank the front pane of glass looks like a mirror? Take a look now if you've never noticed this before. Of course, this doesn't happen if there's no water in the tank, as you can see right through the front pane, even when looking at it through the end of the tank. Anyway, at this point I want to make some basic recommendations related to the topic. 1) If you have a wall of live rock from the bottom almost to the top of your tank, then don't worry about the background too much. Most of the reflection takes place several inches from the top of the tank. 2) If you have considerable areas of glass exposed at the back of the tank, unobstructed by rocks, use a taped on plastic background instead of paint. Or, try putting your tank close to a wall and just paint the wall behind it blue/black. Again, this can result in the back of the tank being as much as 30% brighter than if it was painted. 3) Always keep your glass clean to promote better reflection regardless of backgrounds, which includes scraping away coralline algae. 4) Don't paint the front of your tank For a different look, I put nothing on the back of this 55 gallon tank and just painted the wall behind it blue. The Temperature Effect In addition to the background effect, we also noticed another pattern in the numbers that persisted regardless of the type of fixture. The readings were always lower at one end of any given fixture than at the other end, and if you scroll back up and look at the footprints above, you'll see this. The readings were always a little higher on the left end of the TX5 fixture, and we found that this caused by a difference in bulb temperature from one end to the other. I'll go into more detail on this in a future article, but for now it's enough to point out that the 3" exhaust fan in the fixture was on the right end and it drew relatively cool air from the room into the left end. As the air passed over the bulbs it became increasingly hotter, meaning the bulbs were slightly cooler at the left end of the fixture. Every bulb has an optimal operating temperature, and in this case the bulbs' output fell off a little at the right end of the fixture due to the increase in temperature. While the end to end differences weren't drastic by any means, they were consistently there. It's unlikely that anyone will be cutting holes in a pre-fabricated fixture and/or upgrading the included fans, but if you decide to install a lighting retro-fit kit into a canopy, be sure to use an appropriately-sized fan(s) for the job and give some thought to placing it/them in the top-center of the canopy with vents in both ends. Putting the fan in the top-center and vents in the ends would decrease the distance that room-temperature air travels over the bulbs, and would keep both ends of the bulbs at approximately the same temperature. Test Results for a Fixture with a Single Reflector Okay, let's get on to how we tested some T-5 bulbs with a single sheet-type reflector that has a single fold down each edge, and what we found. To start, we grabbed our Nova Extreme fixture that houses four 48" T-5 bulbs and includes a single polished aluminum sheet mounted above bulbs. Then, we covered the entire reflector with black electrical tape. We put the bulbs in, set the fixture up over our testing rack, and fired it up. One little thing to note here is that we waited about half an hour to start taking readings, as we found that it takes a while for systems to warm up and the light output to stabilize. Again, output changes depending on bulb temperature. After everything was ready, we took a series of readings to measure PAR using our meter. Readings were taken at fifteen positions under the fixture, five from end to end and three across (see the grid on the figures below). Note that the bottom of the fixture was approximately 5.25" inches from the top of the light meter's sensor. After finishing that up, we pulled out the black tape, got the fixture warmed up again, and took the same series of readings. This let us make a direct comparison between the light that would be going down into a tank with and without the reflector. With the reflector blacked-out the highest PAR reading we got was 191 µMol·m²·sec. We also found that the average PAR was 155 µMol·m²·sec, which was calculated by adding all the readings together and dividing the sum by 15. With the tape pulled off the reflector the highest PAR reading was 435 µMol·m²·sec, and the average PAR was 342 µMol·m²·sec. That's quite a difference to say the least, as the average PAR went from 155 to 342 µMol·m²·sec! So, it should be quite clear that the use of a sheet-type reflector can make a heck of a difference in the amount of light going from a T-5 bulb to the critters in your tank. Test Results for a Fixture with Individual Reflectors Next, we tested our TX5 48" fixture that houses five 48" T-5 bulbs with individual reflectors for each bulb. They're the type that has numerous folds, and have a little ridge that runs right down the middle of the reflector, too. This little ridge is supposed to angle away the light going straight up from the bulb, rather than reflecting it straight back down into the bulb. Again, these reflectors wrap around each bulb to some degree, and we expected them to be even better than the single sheet-type reflector. Note that due to the width of the fixture we decided to use only three bulbs in it, so the readings we got were lower than those presented above. This doesn't really matter though, as we were looking for the change in readings with and without reflectors rather than the total output of a given fixture. Again, we covered each of the reflectors with black electrical tape, put the bulbs in afterwards, set the fixture up over our testing rack, and warmed it up. We took a series of readings in the same manner, and then pulled out the black tape, got the fixture warmed up again, and took the same series of readings once again. With the reflectors blacked-out the highest PAR reading was 128 µMol·m²·sec, and the average PAR was 101 µMol·m²·sec, which again was calculated by adding all the readings together and dividing the sum by 15. With the tape removed the highest PAR reading was 451 µMol·m²·sec, and the average PAR was 304 µMol·m²·sec. So, we were right to think these would send even more light downwards, as the average PAR went from 101 to 304 µMol·m²·sec! Thus, again, it should be obvious that the use of well-designed reflectors, individual-types in this case, can make a huge difference in the amount of light going from a T-5 bulb down into a tank. Other Bulbs So, what about V.H.O. bulbs? Do reflectors make as big a difference? Well, all of the V.H.O. bulbs I've ever used had an internal reflector. I assume that's because they have a larger diameter making it easier to add some sort of coating to half of the inside of the bulb to send all the light in one direction. However, we didn't do any sorts of tests on V.H.O.s and I've never broken one open to see what's in there, so I'm not positive about that. Regardless, I don't know of anyone that makes individual reflectors for V.H.O. bulbs. Maybe we'll try a sheet-type reflector with some in the future though, just to see if there's any difference. Likewise, the bulbs used in the L.E.D. fixtures I've seen always come mounted in little individual reflectors, so we didn't test any L.E.D.s without reflectors, either. Metal halide bulbs and the reflectors made for them come in a range of shapes and sizes and finishes, but there's already a good bit of information about these available. Sanjay Joshi has looked at many of them and written up the results in a series of articles (see references below), but what I'll tell you here is that the right reflector can make a huge difference, and the wrong one won't help much. So, if you're thinking about retro-fitting some into a canopy, I recommend you do some homework on bulb/reflector combinations. Bottom Line It is imperative that you use reflectors with T-5 bulbs, and individual reflectors do a better job of sending light into a tank than a single reflector. If for some reason you decided to add some T-5s to a canopy yourself, the data show that you'd need three bulbs without reflectors to send the same amount of light into the tank as one bulb with a quality individual reflector! Also, don't paint the back of your tank, and make sure that your bulbs are adequately cooled for optimal performance. References / Sources for More Information Joshi, S. and Marks, T. 2003. Analyzing Reflectors: Part I - Mogul Reflectors. Advanced Aquarist's Online Magazine: 2(3). Joshi, S. and Marks, T. 2003. Analyzing Reflectors: Part II - Double Ended Lamp Reflectors. Advanced Aquarist's Online Magazine: 2(7). Joshi, S. and Marks, T. 2004. Analyzing Reflectors: Part III. Advanced Aquarist's Online Magazine: 3(3). Joshi, S. and Marks, T. 2004. Analyzing Reflectors: 400w DE Reflectors. Advanced Aquarist's Online Magazine: 3(12). Joshi, S. and Marks, T. 2006. Analyzing Reflectors: Part V. Advanced Aquarist's Online Magazine: 5(2). Joshi, S. 2006. Facts of Light Part I: What is Light? Reefkeeping: 5(1). Joshi, S. 2006. Facts of Light Part II: Photons. Reefkeeping: 5(2). Joshi, S. 2006. Facts of Light Part III: Making Sense of Light Measures. Reefkeeping: 5(3). Riddle, D. 2005. Product Review: A Comparison of Two Quantum Meters - Li-Cor v. Apogee. Advanced Aquarist's Online Magazine: 4(7). Riddle, D. 2008. Product Review: Lighting for Reef Aquaria: Tips on Taking Light Measurements. Advanced Aquarist's Online Magazine: 7(2). View the full article

Click through to see the images. The Elos E-Lite line will soon take a giant step forward. The new Elos E-Lite 3 is a highly modular LED lighting system. In essence, the E-Lite 3 is composed of four separate and adaptable components: A 100% brushed aluminum enclosure. The enclosure includes the main circuit board, LED strip sockets, and an on-board temperature sensor. Individual LED strips. Optional optics. Optional cooling fan. Modular and Adaptable Each E-Lite 3 comes standard with Cree® XP-E HEW cool white LED strips occupying half the available sockets. Aquarists have the option of choosing from a variety of LED strips to fill the remaining sockets. Each LED strip is comprised of varying combinations of the following Cree® diodes: XP-E HEW Cool White XP-E Red XP-E Green XP-E Blue XT-E 457nm Royal Blue The base E-Lite 3 units can be operated without a fan, but an optional central fan is required if aquarists choose to add more LED strips. The on-board temperature sensor automatically adjusts fan speed. Aquarists may also add optional 24° or 48° optics. ∇ Video of modular design Controllable The circuit board contains a four channel dimmer. According to Elos: Designed to be flexible, you can easily control color, intensity, moon light of your light thanks to our sophisticated, yet simple, E-Vision Tempo. By adding the Evision control center, you can use the touchscreen for more advanced functions of your e-lite3 and much more. ∇ Video of controllable LEDs Two E-Lite 3 Models Elos will introduce two (impressively trim) E-lite 3 models: The E-Lite 3S (shown throughout this article) measures 9.6 x 5.9 x 0.80 inch (240 x 150 x 20 mm) and is rated for 6 to 59.5 watts. The E-Lite 3L measures 24 x 2.75 x 0.80 inch (600 x 70 x 20 mm) and is rated for 8 to 109.2 watts. Photos of the E-Lite 3L are not available at this time. It looks like the E-Lite 3 will put out a lot of light for their diminutive sizes! For aquarists seeking even more personalization beyond customizable LED combinations, E-Lite 3 owners can also choose different colors for their top plate to add a stylish flare. ∇ Video of interchangeable top plate Pricing and Availability Elos will release pricing and availability information shortly after Interzoo 2012. As with the new Elos Concept80 aquarium system, we will update you with information when they are released. View the full article

Click through to see the images. The dwarf seahorse is the smallest of the four species found native in US waters measuring only one inch in length when fully grown. Its habitat is mainly seagrass beds in the Gulf of Mexico and these beds have declined since the 1950 and the habitat was further hurt by the BP oil spill in 2010. The National Marine Fisheries Service has agreed to conduct a year-long study of the tiny seahorse to better understand its current state and whether or not H.zosterae needs protection by the Endangered Species Act. "Oil spills like the one two years ago in the Gulf of Mexico exact a terrible toll on marine life, especially species like the dwarf seahorse that were already struggling to survive," said Tierra Curry, Center for Biological Diversity conservation biologist. ... Dwarf seahorses — and other species of seahorse — are far too rare to make any conclusions, said Marine scientist Joel Fodrie. He said 200,000 individual fish caught over five years included only 60 seahorses of all kinds; at least seven of them were caught last year. Let us hope that through intervention the population rebounds. (via Palm Beach Post) View the full article

Click through to see the images. (1920x1200 pixels) Click the download button (above) to view the wallpaper. Right-click the wallpaper and "set as desktop background" or save the file on your computer. Photo by Mitchell Brown. Visit www.aquaticprints.com to view (and purchase prints of) Mitchell's amazing reef photography. PREVIEW View the full article

A 100-fold upsurge in human-produced plastic garbage in the ocean is altering habitats in the marine environment, according to a new study. View the full article

Click through to see the images. Sustainable Aquatics is known for their wide variety of captive-bred designer clownfish. We just learned that the company released a few pairs of their SA Naked Clowns to Alpha Corals, an online livestock retailer located in Wisconsin. According to Matthew Carberry of Sustainable Aquatics, these Naked clowns are not readily available and they don't anticipate another release for quite some time. So what makes the SA Naked Clowns so special? To me, it's the brilliant orange coloration of the body which actually takes on a yellow hue in certain areas. Additionally, the outer edge of the fishes eyes are bright yellow, which one can appreciate only by seeing them in person.

To gain new insights into how dolphins communicate, researchers in Japan created a prototype of an extremely broadband “dolphin speaker” capable of projecting dolphins’ communication sounds, whistles, burst-pulse sounds, as well as detection sounds such as echolocation clicks. View the full article

Click through to see the images. Sustainable Aquatics is known for their wide variety of captive-bred designer clownfish. We just learned that the company released a few pairs of their SA Naked Clowns to Alpha Corals, an online livestock retailer located in Wisconsin. According to Matthew Carberry of Sustainable Aquatics, these Naked clowns are not readily available and they don't anticipate another release for quite some time. So what makes the SA Naked Clowns so special? To me, it's the brilliant orange coloration of the body which actually takes on a yellow hue in certain areas. Additionally, the outer edge of the fishes eyes are bright yellow, which one can appreciate only by seeing them in person.