My 1.5 ft Reef log

[teebs]

Don't count on it.

Each time, it poop about 2 mins. no joke hor.

Hopefully it is pooping only during feeding days.

Else there will be way too much waste.

U know what to do when U want to reduce your bioload...

Upgrade to a larger tank!!!

[raydiative]

U know what to do when U want to reduce your bioload...

Upgrade to a larger tank!!!

wha lau.. Peter you super poisonous...

[jackywongto]

I will only go smaller. not bigger.

Dislike big tanks. don't have the $$ and patience to maintain them well.

Well the biggest I go might be 2 ft max.

had a 2.5 ft and even that I feel it was too big.

What I would like to do is perhaps have 3 separate species 1 ft cube tank but link the water management system together.

1 seahorse & pipefish, 1 SPS and 1 softies + LPS.

[jackywongto]

wha lau.. Peter you super poisonous...

He is just so full of that... hahaha

[teebs]

I will only go smaller. not bigger.

Dislike big tanks. don't have the $$ and patience to maintain them well.

Well the biggest I go might be 2 ft max.

had a 2.5 ft and even that I feel it was too big.

What I would like to do is perhaps have 3 separate species 1 ft cube tank but link the water management system together.

1 seahorse & pipefish, 1 SPS and 1 softies + LPS.

Wah Lau...3 tanks linked together...

If each is a 1.5 cube then ur total tank size will be 4.5x1.5x1.5...

[teebs]

wha lau.. Peter you super poisonous...

Upgrade tank to reduce bioload also super poisonous...

[jackywongto]

Wah Lau...3 tanks linked together...

If each is a 1.5 cube then ur total tank size will be 4.5x1.5x1.5...

I am quite sure you will fail your maths and comprehension if you go back to pri school.

it will be 3x1x1 ... haha

[teebs]

I am quite sure you will fail your maths and comprehension if you go back to pri school.

it will be 3x1x1 ... haha

Ah...1 foot cube... So quarter of my tank size lor...

[jackywongto]

More about clams by David C Potts.

Some Basic Biology

Clams are rather simple animals anatomically. They have two shells, and very basic organs and organ systems. Their most remarkable feature is their algal symbionts. Clams have a shell (duh). Two shell halves are connected at the bottom by a joint that consists of 4 "teeth" that interlock. When viewing a clam from the bottom, you will notice a large hole, this is the byssal orifice. Clams build their shell by uptaking calcium from the water, much like stony corals build their skeletons. The adductor muscle is connected to both halves of the shell, and is responsible for the opening and closing of the two halves.

Clams have a very simple cardiovascular system, a small heart, with two main arteries and two main veins. They have gills, which provide for gas exchange and filtering of small food particles, and kidneys for the removal of toxic metabolic byproducts from the blood.

Clams possess a very basic nervous system, consisting only of nerve ganglia (bundles) which control the organs and organ systems, and also receive sensory data from the clams iridiphores (eye like organs). Notice when you pass your hand over a clam creating a shadow, the clams closes up. The iridiphores can only sense the amount of incoming light.

Clams do have a digestive tract and excretory system. Suspended food particles from the gills where they travel down nutritional channels to a mouth, down the esophagus, and into the stomach where the food is broken down. The foodstuff is then passed to intestines where nutrients are absorbed and waste excreted through the anus. The kidneys secrete toxic waste into the outcurrent siphon.

Sexually, clams are simultaneous hermaphrodites, meaning they all possess both testes and ovaries. However, whereas the male gonads are active when the clam is young, the ovaries are only active when the animal has reached maturity.

Of great importance to the smaller of the tridachnid species is the byssal organ and gland. They byssal organ is secured within the animal by four muscles. Threads are produced by the gland which secure the clam to substrate. This keeps them from sloshing around in the ocean current, and helps to keep them situated for optimum exposure of the mantle to light. Which bring us to the mantle and the algal symbionts. The mantle is the part of the clam with the gorgeous colors and patterning. It can extend and recess into the shell halves. There are two parts of the mantle, a lateral mantle which is attached to the sides of the shell, and the syphonal mantle- the pretty part us clam freaks lust for. The syphonal mantle has two openings, the big incurrent opening, where water passes in and goes through the gills, and the excurrent opening, where water is expelled.

The zooxanthellae are housed here in the syphonal mantle, as are the iridiphores mentioned above. Zooxanthellae are microscopic algae, and can produce fabulously colored pigments, most likely the purpose of these pigments is to protect the algae from harmful UV rays.

Tridachnid clams differ from most other bi-valves with this symbiotic relationship. Clams carry up to 10x the number of these symbionts per square (insert convenient unit of measurement here) than corals. They can change the population density apparently by phagocytosis, and possibly also excreting them through the channel system. Up until 1992 it was assumed that these zooxanthellae were housed in the blood vessels of the mantle. This seems reasonable as it would give an easy explanation of how the algae transported nutrition to the clam. A big wrench was thrown into the works when it was discovered that the algae live in closed channels which run from the mantle into the stomach. In juvenile clams the zooxanthellae first appear in the stomach, so it can be hypothesized that the zooxanthellae then travel an upward path into the mantle.

The big question is: how does the algae get the nutrition to the clam? Its possible that the products of photosynthesis and the dark cycle which produces carbohydrate travel down the channel system into the stomach. Its unclear to me, and apparently unclear to Knop after reading the book, exactly what mechanism is responsible here. Hopefully a few weeks sitting in the bio library will yield more answers on the role of zooxanthellae in clam nutrition.

[jackywongto]

Differences in the species of Tridachna clams.

T. crocea is the smallest of the giant clams. Typically they grow to 5-6 inches in length. Croceas live in dense colonies in shallow, and intensely lit areas. This accounts for their often beautiful blue and green pigmentation. Croceas can dig themselves into rocks by using their smooth "file like" shells mechanically in combination with acidic secretions to soften the rocks. The shells of T. crocea are typically football (american football) shaped, and although typically smooth, the uppermost part of the shell may have pronounced growth scales.

T. maxima can reach a maximum of 12-16 inches, but adults are often a little smaller. They are also considered to be "high light" clams, and can have blue and green mantles, like T. crocea. T. maxima has much more pronounced growth scales on its shells, and the shells are longer than T. crocea. Maximas are generally considered to be the hardier of the two.

T. derasa can reach up to 50-60cm long. Although not immediately as striking as maximas or croceas, they are very handsome in their own way. Nice specimens have a fluorescent blue rim around the mantle. with blue and yellow lines on a goldish background. Derasas have smooth shells. T. derasa come from 4-20m deep waters, the outer edge of the reef.

T. squamosa reaches 20-24 inches long. Their mantles are speckled with greens, blues, browns, yellows, and orange spots and bands. Most of the ones seen in the aquarium trade have greenish dots, on a light brown background. The shell of squamosa is very distinct in that its scales are very pronounced. Squamosa comes from a depth of down to 18m.

T. giga is the largest of all the clams, with the largest shells of the speciment measuring almost 55 inches long. Giga has a smooth shell, and usually a lime green mantle, with small blue spots. T. giga comes from down to 20m deep.

Of these clams, T. crocea is generally considered to be the most difficult to keep, followed by T. maxima. I suspect this may be due to their high light requirements.

[jackywongto]

Keeping the giant clams in the home aquaria:

Probably the most important element to consider here is lighting. T. max and T. crocea typically come from highly lit areas. Knop recommends using metal halide lighting, and perhaps actinic supplementation, and I happen to agree. I know people who have kept their maximas and croceas under NO, VHO, and power compact fluorescent lighting, but I also know quite a few who have had their clams lose intensity, and in some cases starving to death over the course of 6 months to a year.

Maximas and croceas typically have a higher density of zooxanthellae, and rely heavily on the nutrition provided by the algaes. This may account for the successes of people keeping these species in high light, low plankton (big honkin' skimmer) tank along with SPS corals. Derasa, squamosa, and giga all come from deeper in the ocean, and therefore have less of a light requirement than crocea and maxima. I could go into a long scientific discussion about lighting a home aquaria, but I believe that has been covered at some point in our lecture series.

If it hasnt, the bottom line is that we must try our best to duplicate the settings that our animals came from. 2 40w bulbs over a 55g aquarium isn't even coming close to the amount of sunlight a critter from 10 feet under the water is usually getting. According to the lectures here and on fishroom by Chris Paris, we typically don't even get close to natural light intensity in home aquariums, even when we have MH lighting.

Synopsis: Maximas and croceas need a bunch of light. Expect your clams beautiful pigmentation to fade if you don't have it, and expect the clam to die.

Derasa, giga, squamosa come from deeper waters and you can obviously get away with less light (although you will want to favor the blue spectrum in your lighting arrangement).

Water Current: Clams need water current, but they don't like strong, direct current.

Calcium: Clams need 400-450 mg/l calcium, and 7-12 dKH hardness according to Knop. This can be achieved by kalkwasser dosing, Ca reactor, dual part additives.

pH: Knop recommends a range of 8.0-8.1 as optimal with 7.9-8.2 as the extreme ranges. Most well run reeftanks these days run at 8.2-8.4 pH, and I haven't yet seen a problem under these conditions.

Additives: Here we run into the ever present problem of how-much-of- this-element-does-our- organism-need. We know the animals use them, we don't know how much, although with the advent of cheaper, more accurate test kits we may be able to figure it out.

I add a full spectrum trace element product, strontium, and iodine in the form of lugols solution. Knop only says to add trace elements, and that's as far as he goes. He also advises to add vitamins in the form of a concentrated liquid. I'm not sure I agree, but I'm hardly at the level of Daniel Knop, so I'll shut up about it.

Water temp: Knop advises to keep the tank between 25-32 deg C with 22 to 34 being the extreme range. The main concern here is keeping the water temp stable as the clams react poorly to sudden changes.

Water Quality: Things get kinda weird here. Everything we usually think about in terms of keeping a reeftank is contraindicated. The symbiotic zooxanthellae of the tridachnids need nitrogenous waste as a fuel. The waste produced by the clam itself though filter feeding is utilized as a source, but such filter feeding may not be taking place in a highly skimmed aquarium. Knop suggests ~2ppm nitrate as being optimal. Dick Perrin likes (as of a year ago at least) to keep his nitrates at ~8ppm. This can be added in the form of a sodium nitrate solution, or an ammonium nitrate solution.

I'm sure this is gonna come up, so I'll just cover it now: yes, anecdotally I have heard of the usage of human urine as a source of nitrogenous waste in clam farms and tanks (by sober people no less).

The other concern here with water quality is that most of us employ pretty heaving skimming. Clams are built to filterfeed. Knop recommends using a solution of baking yeast and water, or a commercial preparation. Unfortunately I haven't seen such a preparation available in america. I have seen a planktonic algae preparation available though. Knop also discusses the use of blood as a food source. For those of you unfamiliar with phlebotomy, I suggest you consult a medical professional before attempting this <<grin>. I have not as of yet spiked a vein for my clams, but it is an interesting consideration. Knop mentioned the problem of possibly spreading pathogens through this method, although unless the host providing the blood was in a state of septicemia, I don't see it as a huge concern.

Anecdotally, I know of people keeping T. maximas and T. croceas in heavily skimmed SPS tanks for about five years (and still going strong).

Purchasing a clam: When purchasing a clam, be very particular in choosing one. Look closely at the mantle for any signs of bleaching at all. Pass your hand over the clams to see if they retract in reaction to the change in light, if they dont, pass the clam up. Look at the byssal opening for any signs of injury or tearing. I've seen clams in such bad shape that there was no byssal organ at all, just an empty hole. If you can, look under the mantle for parasitic snails.

Gently acclimate your clam to its new lighting. It may have been sitting in the dark for a few hours during shipping, or under inadequate lighting at the dealers. Shield it from intense light, gradually working your way up full light. Typically I use a sheet or two of "eggcrate" light diffusing material.

I just set it on the tank over the clam, and every few days I leave the eggcrate on for a little less time. There is no real set amount of time on this. Observing your clam will be your best guide.

Placement of clam: Place the clam with the mantle up towards the light. Alot of times you will get your clam already attached to rock or a clamshell, or something else. This may or may not make your life easier depending on your tank. You can either place the clam somewhere and observe it for signs of good health (mantle expansion, not trying to move), or you can cut the byssal threads.

This is done by poking, prodding, tapping the soft tissue surrounding the byssal threads. If all goes well it will retract and reveal the byssal threads. Take a sharp instrument, and cut the threads. You must be careful not to pull the clam from its attachment, or irreparable damage may be done to the byssal organ, in which case your clam may be a world of trouble. I have heard of some croceas and maximas living after losing their byssal gland, but the chances of survival are slim to none IMO. After the threads are cut, place the clam where you think you want it to be. Don't wedge it into a rock, or it will not be able to open fully. Place it on a rock shelf, or possibly the substrate. This is a long standing argument about placing a clam on the substrate. Some warn of bristleworms. Knop thinks there is some chemical defense mechanism that clams employ to keep the bristleworms away. I've heard of clams being on an aragonite substrate for 3 years now with no problems. I personally don't see it as being a big threat. It may take months to figure out where your clam wants to be. Observing it will give you a sensitivity to its "moods", and eventually you'll get it figured out.

Do _not_ glue, cement, or epoxy your clam to anything if it keeps trying to move. Just keep trying.

Problems: There are alot of pathogens and a few parasites that can injure a clam in the home aquaria. I am only going to go over the most prevalent.

Pyramidelline snails can be a problem. They prevented me from getting one of the nicest croceas I've ever seen. Even worse, they can injure or even kill a clam. These are small elongated snails with whitish shells. Look for them at night feeding on the mantle of the clam. If you have them, pick them off by hand. Juvenile coris wrasse and the sixline wrasse both predate these snails and can be utilized to fight off the little buggers. (unfortunately they also decimate the copepod population of a reeftank).

Murex snails bore their way into the clam shells by dissolving the shell. Personally I have never observed these snails, so my advice is that if you see a snail trying to munch through your clam shell, remove it.

There are infectious pathogens that can infect a clam. Of those that have been documented, are Vibrio sp, Ricksettia, and Perkinsus. The bad news is that Knop says there is no hope.

I'd be interested in knowing if Dr. Bingmans chloramphenicol protocol used with RTN cases in SPS would be effective against Vibrio infections.

Environmental factors also play a part in clam pathology. Generalized bleaching can be caused by lack of nitrate. Localized and central bleaching can be caused by damage from subjecting the animal to light conditions without proper acclimation.

Knop also lists damage by heat, cold, low salinity, high salinity, heavy metal poisoning. I see little need to go into the details on those.

That pretty much concluded my lecture. I've covered most of what I consider to be relevant to the hobbyist. On the other hand, I've barely scraped the tip of the iceberg.

I suggest if you are seriously interested in clams to not only get Knops book, but to read everything you can find, and talk to everyone who will talk to you. Unfortunately, there isn't a vast body of scientific information on the Tridachnid clams, but hopefully with all of the efforts of captive propagation, research will continue to increase and we will unravel the mysteries of these beautiful creatures.

Question: Why the low recommended pH?

<dc> I have no clue. I assume it is the pH that Knop kept his tanks at, and concluded that it was optimal. I personally dont find any problems keeping my tank at 8.3-8.4.

Question: Is placing clams on the sand in anyway detrimental to them?

<dc> Not that I have observed, or heard of anectdotally. again, there may be a concern of bristleworms, but I personally think the threat is overrated.

Question: What exactly are the symptoms of a Vibrio infection?

<dc> Internally, I dont know. Externally there may be visible yellow pustules. From the info I have gathered from Bingman, Vibrio sp. acts fast, and can "reduce an animal to a putrifying mass of amino acids in short order"

Question: Given the delicate nature of the bysal organ, how often should you attempt to move your clam to a "better" spot?

<dc> as often as it falls down seriously, the clam will situate itself when it is content, otherwise it wont make a serious attempt to attach itself. Most of the tridachnids are even capable of a small amount of movement, so just observe the clam. Eventually you tune in to the needs of your animals.

Question: If clams are in nature filter feeders, can you feed clams in your aquarium? If so, what would be a good food and how do you go about feeding them?

<dc> yes, you can. As I mentioned earlier Knop recommends a solution of baking yeast and water. Unfortunately thats as specific as it gets. I will try to contact him and find out the specifics. There is a planktonic marine algae preparation that can also be used, and of course the blood thing. The main concern here is that you turn off your skimmer for a few hours while feeding

Question: Are any of the infectious pathogens you mentioned species specific?

<dc> of course, clams would probably do very well in a planktonic friendly tank, such as the algal filtration tanks

<dc> Different species of the different bacterias have been known to attack various organisms. For instance a species of Vibrio is the cause of cholera in humans I believe. I dont know if the particular species of bacteria that infect clams are zoonotic though.

<dc> or vice-versa

Question: In the grand scale of reef keeping (mushrooms through SPS) how difficult would you rate the keeping of giant clams, using a 1-10 scale?

<dc> good question. I dont find them difficult at all to be honest. The trick is to use alot of light, and calcium additions. Healthy clams with nothing in a tank to predate them are usually no problem at all.

Question: It is recommended not to put clams within crevices etc, but in nature several of the species are actually burrowing. Isn't this a contradiction?

<dc> not at all. the clam makes its on hole according to its needs. Shoving a clam in a crevice is according to the hobbiests need.

Question: Know of any good clam web sites or other resources on the Web?

<dc> for purchasing, or learning about them?

<dc> there is a very nice site with good pictures and some info

<dc> some of my clams are even on the site

Question: You touched on the concept of dosing a clam tank with nitrates, have you found that to be necessary/beneficial?

<dc> http://personal.trxinc.com/jspece/reef1/clam/clamindex.html

<dc> I've only been keeping clams for about a year. my tanks run at 0ppm nitrate and I have never had a clam expire for no reason. The clam itself may be producing enough nitrogenous waste to provide its zooxanthellae with nitrate

<dc> and I frequenly urinate in my tank when going all the way to the bathroom is inconvenient

* dc grins

Question: Do clams usually require acclimation to light when you first get them?

<dc> I would follow the recommendations of Knop and Perrin on this subject, and keep nitrates in the tank, particularly with a tank heavily stocked with clams

Question: When placing additives in the tank, is it easier to stand on a stool or do you use the "arcing" method?

<dc> yes, I use eggcrate over the tank to diffuse the light when I first get them. ramping up the hours with the light cycle might also be of use

<dc> I use the arcing method. In podunk Missouri I was the pissing for accuracy champion 3 years running.

[poomoon]

this is good bro ... really doing research. a very passionate reefer

[jackywongto]

some much info on the web.... you can read and read and nvr be finished reading.....

[teebs]

some much info on the web.... you can read and read and nvr be finished reading.....

Wah lau eh...u really free leh...

[jackywongto]

multi multi multiple tasking.

[teebs]

multi multi multiple tasking.

wat time u going comy's hse today?

[jackywongto]

wat time u going comy's hse today?

maybe cannot go. gotta take care of baby and fetch girl from child care.

promised to bring her to pasar malam.

not to mention have to wash their bedsheets, mop the floor, clear the bills,pack the storeroom.

[poomoon]

maybe cannot go. gotta take care of baby and fetch girl from child care.

promised to bring her to pasar malam.

not to mention have to wash their bedsheets, mop the floor, clear the bills,pack the storeroom.

multi (100x) tasking ...

[teebs]

maybe cannot go. gotta take care of baby and fetch girl from child care.

promised to bring her to pasar malam.

not to mention have to wash their bedsheets, mop the floor, clear the bills,pack the storeroom.

Ahhh...tat reminds me...I got to find some time to pack the store room also...

Tmr want to go Reborn? Want to go get my cleaner shrimps.

[jackywongto]

http://somas.stonybrook.edu/~MADL/pubspdf/...-clamgrowth.pdf

those who have clams can read this.

[jackywongto]

woke up and found my clams toppled over.

I have inserted a plastic backplate behind the rock to prevent them from shooting themselves off the rock again.

They have been there the last 7 hrs.

Hopefully they will stay there and be happy.

Gonna remove the place only 2 days later.

[jackywongto]

okay for those going to CF to get the clams.

When you choose the clams from the top down look, the colour is about 20 - 30 lighter as compared when you look from the side of the tank.

So a greenish blue clam that you choose at CF when viewed from your tank through the glass will look blue.

An electric light blue will look blue when viewed from the tank.

To choose a healthy clam, place your hand over the clam to block out some light, the clam should retract.

It the edge of the shell is white and looks new, those are growth.

choose the brighter coloured ones.

[FuEl]

One of the best foods for clam is microalgae. For those on budget, check out Shellfish Diet from Reed Mariculture. Pay a bit more but the algae lasts a long time.

[jackywongto]

One of the best foods for clam is microalgae. For those on budget, check out Shellfish Diet from Reed Mariculture. Pay a bit more but the algae lasts a long time.

anyone wanna share this with me

don't mind trying.

I am feeding DT phytoplankton every other day atm.

[peacemaker]

some much info on the web.... you can read and read and nvr be finished reading.....

Ahem... *cough* Should research before buying, not after. Many of us are guilty of this, including me.

I would love to keep clams some day, but I'm a bit worried on the calcium in-take in a nano tank. Do let us know how frequent you need to supplement to keep your clams happy?