Hi everyone,
What a great thread! Quite a long read at 53 pages but it brought me up to speed.
Ive been needing to get rid of nitrates in my
freshwater aquarium...will a sulfur denitrator still work in freshwater conditions?
The problem is its quite a small tank (200L) and some what over stocked and Im not too keen to throw fish out
So yeah... it get nitrate up really quick in there.
The best I can do to control nitrates (with only a once a week water change) involves greater than 50% changes which is not very good (pH swingss etc). So Ive been researching denitators. The simple ones which are basically are a coiled pipe (~25 foot long) that has slow water flow through it seem to be pretty much useless - further more this type or any type of denitrator besides the sulfur denitrator require the bacteria to be fed with alcohol/glucose which is a pain. So now after recently discovering the sulfur denitator which requires some what minimal or long intervals between servicing makes it ideal for me
Also I wont have to add glucose/alcohol either as the sulfur is the energy for the bacteria. This coupled with the short cycling times means I just had to build a little "proof of concept model" which is what I did...
I used a 3 litre juice bottle which was 50/50 filled with sulfur and crushed coral (the only CaCO3 compound available locally) and I put a T junction on my canister filters output which went to feed into the bottom of Juice bottle (via a 19mm hose) The output from the top was an air hose which went back into the tank. To regulate flow I used air hose valve (the one that squashes the hose).
Initially I left the unit fun on full flow to pretty much clean out the media and air pockets (all of this went into a bucket). Once done I set the unit to 1 drip per second and connected it to the tank. Its been like that for ~33 hours and so far the denitrator output is a slight shade lighter than the tank (ie less nitrates from the denitator).
Id get a photo - well in fact I did, but Its giving me hell trying to upload it to imageshack or photobucket. Anyway, the output from the denitator has less nitrate than from the tank. (Tank is sitting at ~20ppm).
More so, my cheapo "proof of concept denitrator" doesn't have a recirculator pump meaning that cycle times should be longer? or efficiency will be less? or both?
ATM Ive got around 1.3L of sulfur and once gravel rockets etc are taken into account my tank has only 175L of water in it. So I'm pretty close to the 1% of tank volume rule.
So whats left for me to do now? My plans are to wait until nitrates reach zero from the denitator output and then increase flow a bit. If then my little experimental denitator is a success Ill build a proper one.
However, should my nitrates NOT reach zero does anyone have any ideas of what to do? Does any one else use a sulfur denitator for fresh water aquariums?
