Achilles Tang

Interesting... yeah... I guess competition can really drive down the prices. Wish I can have my own private cargo jet and fly back everything!

Upgraded to Alvyfoamer 648. Decided to change my mind and sell off my H&S skimmer. Sorry guys, but I can't remember who asked me to put them in the queue... I need to search my PM inbox again. So priority given to those who asked me before to sell them the skimmer (that is, if you still want it) and the highest offer secures it! The H&S skimmers have good resale value so I won't drop the price too much. Pls PM me your offer. Thank you! AT

Boy bands or girl bands? Just kidding! Phang may be selling off his RA680. Or for a new set you can call Edmund of eAquaNature (click banner above). I also got lobang for RA680 but I dun know if I can spare the time.

Presenting Mr Donkey Dung! I surprised him late last night when the lights are out. Chomp chomp chomp Nice little piles of clean sand left behind!

Yes, that restricts airflow so the bubbles are finer.

Looks like we are still going around in circles, before we get lost, let's state the things we want to discuss abt: 1. Whether or not to have a sandbed ie. looks vs function. 2. How deep a sandbed should be for maximum nitrifying effects. 3. How to minimise sand clumping that could lead to less efficiency and potentially a tank crash. 4. How to encourage/replace more sand fauna /prevent loss of sand fauna. 5. Whether having a sandbed outside of the main tank can work as efficiently as opposed to having one in the main tank. So my opinions again: 1. Whether or not to have a sandbed ie. looks vs function. Having a properly setup DSB will help reduce NO2 and NO3 to very low/undetectable levels as opposed to no sandbed/shallow sandbed. 2. How deep a sandbed should be for maximum nitrifying effects. Using #1 sand (local context), to MAXIMISE the efficiency of nitrifying bacteria that only grows in the anaerobic layer of the sandbed (deep deep down), it should be min. 6 inches which is already a compromise since the reef gurus are advocating that depth already using oolithic sand. Using any lesser depth would create more oxygen diffusion and therefore less nitrifying bacteria will be supported to process nitrates to harmless nitrogen gas. 3. How to minimise sand clumping that could lead to less efficiency and potentially a tank crash. Wei's emphasis on sandbed creatures to stir up the upper layers is unargueable. It is important for these to be present to stir up the sandbed in their own little ways. 4. How to encourage/replace more sand fauna /prevent loss of sand fauna. As stated, people build small pod 'piles' to encourage pod populations from declining. Actually, with the amount of LR present in reef tanks, it doesn't take much of the fauna to migrate to the sandbed to do their work. To introduce more sand fauna, we can only buy quality liverock and macroalgae clumps to replace declining populations as we don't get 'detrivore kits' here locally. Feeding live phytoplankton will encourage the entire food chain to grow from bottom up. phytoplankton -> zooplankton -> pods -> fish. To prevent total loss of sand fauna would mean no predators ie. fishes as the main culprit. It's unrealistic. Sea cukes do not consume pods or worms. 5. Whether having a sandbed outside of the main tank can work as efficiently as opposed to having one in the main tank. Experiments are underway on whether a seperate sandbed placed in a sump or refugium will work better than having it in the main tank. However, it is understood that you will need a larger or equal tank holding the DSB to the main tank's volume. Also unrealistic. Taking a cue from RC reefers, they have huge tubs of DSBs which they plumb to their main tank. With the 'under the stand' sump configurations that we normally have... we cannot provide the volume needed and therefore compromise on sandbed efficiency already. Also you need to ensure that a high flow of water is needed to carry down detritus to the sump or refugium to work properly. Normally a refugium should not be having a high flow of water so as to create a peaceful refuge for microfauna to grow. So that means having a sump to hold the DSB. How big is the typical sump, especially after all the partitions are in and equipment like pumps and skimmers are placed inside? Therefore, for a 'out of main tank' DSB to work, you need: 1. A large volume tank to hold the DSB. 2. You need ample water flow to bring detritus down to the DSB for it to effectively process it.

Yes, sch 80 parts. You can use the cheaper, lighter ones provided they fit well... and you have to go with sch 80 to go with the better gate/ball valves that sch 80 has.

Uhh... that's a very very liquid skimmate. You will lose a lot of salt this way. Try to go for drier skimmate.... and darker... like this:

Ah Wei, Ok so after all the hooha... you just meant to say that a sandbed is only as good as the amt of life it has??? Aiyoh... ok lah. All this talk abt recommending different depths is pointless. Less is not as good, deeper is better. Proven. So the statement: 1) Inefficient breakdwn of NO3 due to hamper of diffusion within the sandbed. (claim by Bob Goemans) ... is untrue. That is how it is supposed to work. Deeper sandbeds cause anaerobic conditions for bacteria to process NO3. shallow sandbeds do not. So moving on... Not true... I have never heard of DSB crashing after 2 or 3 years due to sand clumping. Even when parts of the sandbed has unfortunately clumped together, it is still porous. I heard of someone taking a piece of clumped sandbed and pouring water thru it... water still goes through at the same rate. It is like a piece of rough sponge.... just equally porous. Have you actually tried it? So it is still in effect very much like LR but much more porous. And LR do get clumped up with detritus too, FYI. That is why people recommend blowing off detritus to clear the holes. And please, I studied geography before, aced it too. Compressed rock is caused by geothermic pressure or simply crushing pressure from tectonic activity. It would take lots of heat and tons of pressure to fuse sand into a solid mass of stone and that alone takes years or in the molten heart of a volcano. That simply cannot happen in a reef tank. clumping caused by bacteria activity doesn't produce granite or sandstone. Moving on to life in sandbeds.... Pods are not the only creatures that live in sandbeds, all kinds of worms do too. And worms do not get eaten as quicky as pods. So how now do you propose that we keep our sandbeds as populated as possible? Keep no fishes?

Yes, in all local context, 6" DSB commonly refers to 6" of #1 sand as this is commonly graded in LFS. Because of the 6" deep DSB of oolithic grain size recommended by Dr Ron Shimek, our #1 sand would barely sufficient at the same 5 to 6". Perhaps at #1 size, it would be properly functioning at 7" to 8"? So the difference between Wei's recommendation for a 4" DSB and a 6" DSB is quite major. Not having that extra 2" of depth could reduce efficiency in terms of nitrate reduction as 4" of #1 sand could allow more aerobic bacteria as oxygen diffusion is much easier due to the larger grain size. I know that is impossible knowing how deep our tanks are... but IMO, as the sand compacts over time, less oxygen would be following through and nitrification would happen due to it. IMO, DSBs are like LR which in their inner core, anaerobic bacteria would be present to process nitrates. It works in Berlin systems where you require a lot of LR for this to work. With DSBs, sandbeds are much more efficient at processing nitrates... it can be treated like a big piece of LR (IMO, small LRs do not process nitrates efficiently... only bigger ones do. Logic dictates this). As for Wei's concern abt sand clumping, if there is not enough sandbed fauna, there is not enough sandbed fauna. 4" or 6" or 8".... it will all still clump if conditions are right. As for sandbed fauna.... these can be encouraged by building little 'pod piles', basically stacking some small pieces of LR together so they have shelter for predators where they can grow and hide. Introducing new pieces of LR or macroalgae will often repopulate the sandbed and rocks. A sandbed does not need sand fauna to be properly functional... it needs bacteria. The sand fauna is there for 'maintenance'. Sand fauna does not process nitrates or nitrites... it's bacteria that does the job. A DSB 'eats' voraciously. You will hear of people 'feeding' DSBs. Why? Because DSBs can 'starve'. DSBs allow people to stock more as a tank with DSB process nutrients faster than a tank without one (or a poorly setup one like 1" or 3" - not here, not there). Using sea cukes don't eat detritus fast enough, whereas DSBs process them faster. That is why DSBs are capable of reducing nitrites and nitrates to almost undetectable levels and why people with shallow sandbeds, coarse sandbeds and canister filters can't seem to maintain low levels without a lot of work. I can't see why Wei doesn't advocate DSBs, or at least one more than 1" or 4" (bearing in mind we use #1 sand), with all the benefits like high nutrient-reducing capabilities, low maintenance, micro-fauna friendly environment that a properly setup DSB or Plenum system brings.

Ok... this is gonna address some concerns abt DSBs... Taken from Dr Ron's forum: How do you prevent hydrogen sulfide buildups in a DSB? You don't, cause it normally doesn't build up. Sulfides are produced in anaerobic condtions, but they are oxidized in aerobic conditions exceptionally rapidly, and they also go to bind toxic trace metals. The only way hydrogen sulfide can build up to anything like lethal levels would be to bury a large piece of flesh at the bottom of the tank, and enclose it there until it had rotted away. This simply doesn't happen in reef tanks. -------------------------------------------------------------------------------- quote: -------------------------------------------------------------------------------- When a lot of echinoderms spawn they release chemicals that are toxic to fishes, or they release eggs that are poisonous to fishes. If hydrogen sulfide poisoned your tank, 1) it would not be selective- this stuff is more toxic on a weight per weight basis than cyanide. The tank would be dead, not just one fish. Secondly the room would stink - really stink of rotten eggs. In general, one cannot build up enough of the gas in a tank to poison anything. ---------------------------------------------------------------------------------

How much is the Alvy-Nurse? *suck suck suck*

You're welcome.

Here's what it looks like. The hose is attached to the pump inlet and the other end goes into a hose adapter which is connected to pvc piping. Metal hose clamps are used to tighten the hose around the hose adapter/inlet to prevent accidental slippage.

Looks interesting! How much does it cost? If it's powdery... does it get blown up easily?

This is actually very simple to DIY. It's simple and effective.

Look for Alvy. Highly recommend his work, especially for big beckett skimmers. I think the medium ones, Schuran or H&S should be top of the line.

For clean WHITE sand... use bleach!

more air in, bigger bubbles, wetter foam, more liquid tea-colour skimmate. lesser air in, smaller bubbles, dryer foam, drier skimmate and darker in colour.

? what do you mean?

These are called loc-lines. I bought them at Bangkok chatuchak market at a few bucks only... maybe around S$8 or $10. Cheaper imitations. All black. These can be broken apart by hand. The original loc-lines, you need a special tool as the fittings are meant to be extremely tight. I believe you can find these in Singapore.... I thought I saw a Loc-Line logo at a workshop at Jln Besar Rd, going down to Sim Lim.

Your pix was too big... 1280 width... i reduced it to 700. You are going to be the next one to drink one cup of skimmate for this breach. hee hee! Hmmm... interesting pix! How long has the system been up? I heard the Nautilus is a very hard to keep species and should be kept on their own. They are hunters and prefer tanks which are not brightly lit. I doubt if they eat just brine shrimp. I think seahorses might become lunch too! They come in occasionally at Pacific Marine. Don't recommend any hobbyists to keep them. Besides, I find them spooky looking, their eyes remind me of mantis shrimps, praying mantis.... one big orb and one tiny dot as the pupil.... eeks! AT

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