Nitrate problem

I HAVE POSTED THIS IN ANOTHER SECTION but i would love to see the answers i would get to see if anything helps out.

I currently have a 40 gallon acrylic tank which was started at the end of october of 2010. It has 1 white t5 bulb and 1 blue bulb. Current temp is at 76 degrees. I have 25 to 35 lbs of cured live rock (under a bit for what i should have from the typical 1 to 2 lbs). i have a few soft corals but nothing out of control or overstock wise. Some leather corals and frogspawn and zoo's. I have one clown fish and a blue hippo tang (very small right now) which are the only fish. i have 3 snails 1 turbo (i had another turbo that just died the other day i believe from nitrates) and 2 smaller ones and 3 red legged hermit crabs and 1 emerald crab. 2 power heads for water flow. i have a eheim canister filter with media and eheim substrat. i have a octopuss skimmer rated for a 80 gallon tank. My nitrates are at 20 ppm and i did a 50% water change. the nitrates then went down for about a week to 10 ppm. They went right back up to 20 ppm again. i dont understand why. The corals seem to be affected slightly but my fish seem just fine. i run my lights for about 10 hours to 14 hours aday (going to cut them back) all other levels are fine ammonia is at 0 so are nitrites phosphates are at .25 calcuim is at 520 and ph is anywhere between 7.8 to 8.0 never seems to improve either not sure why. i have accounted for all livestock nothing has died. i do use RO water and it has been tested to be just fine level wise. what can be causing my NITRATES???? i really need help here im at a loss for words or ideas i have done alot of research and can come up with no solution so far. Thanks for any advice in advance

 

i dont think 20ppm is anything to do anything drastic with, i wouldnt do more then a 25% water change at a time. a 50% can be pretty stressfull.
that said you do want i to come down at least a bit

i would start with your canister filter. i am guessing there is some sort of foam or filter floss as a prefilter that is collecting detrius and holding it. It becomes a huge and constatnt source of nitrates.

you should change your pre filter every week.

might want to consider ditching the canister filter, or kinda using it a reactor. reaserch this a little more before you do thought. probably need more live rock. and need to ween it out not just yank it

 

i do use filter floss but it gets changed everytime a water change is done (weekly)

 

i used chemi-pure eilte to get over the 20ppm hump in my nitrate battle. only for a couple months, once i got down to undetectable i stopped and it hasent gone up. might be worth a try

what kind of sand bed do you have??? is there any low-flow low O2 areas in your system for anerobic bacteria??

 

I'm sort of havin the same trubbles so im following along to hear the same advice
All params good except for nitrate hovering arround 30 ppm I am using a canister filter on a 55 g corner bowfront

 

Well, i thought water changes would do it but i guess not. I think it is something that is in your filter or sand cause those things are a few of the only things that don't get removed in a water change. Do you siphon the sand while doing water changes?

 

i just read another thread of yours. you mentioned you used live sand. if this was scooped out of another tank it could be loaded with nitrates. not a huge deal but you will have to do water changes while your sand bed settles down. (as far as creating aerobic zones)

i would also use caution in siphoning a sand bed. depending on depth its cool so long as you only do the very top layer. dont disturb the stuff on the bottom. i am a fan of leaving the sandbed alone and leave it to the clean up crew to turn over.

 

I normally don't touch the sand bed not worth stiring up since my crabs seem to do a great job I have really good flow in my tank right now between my filter 2 powerheads and skimmer so no dead spots I never heard of chemi pure but I'm not a big fan of dosing my tank with chemicals if it can be avoided but I was told if I increase the bacteria with dosing that it should eat the nitrates right up would this be true I know they feed off nitrates. Also I plan on doing 25% water changes weekly and cleaning the cannister filter out as well hope that it helps

 

How often are you feeding your fish/corals?

 

Socal,

Nitrates are a challenge for many reefers. the bacteria they require to be removed live in Anerobic environments (oxygen deprived). this is usually deep inside the rocks themselves. having more rock gives more of these areas, but with a high flow tank, it can be hard. in my experience, there are 4 ways I have seen to lower y our nitrates

1. Refugium or algae scrubber. here you use Macro algaes to pull the nutrients out of the tank.
2. Coil denitrator. in this method you ahve a long (60Ft) lenght of tubing with water slowly going thru it giving you an anerobic place for hte bacteria to colonize in the last part of the coil.
3. Carbon dosing with Vodka, Vinegar, or solid pellets
4. water changes. this removed them and basically dilutes their concentration in your tank.

I use Methods 2 and 3. I have ZERO nitrates on my tests. In addition, an old established tank (my 75 was 10 yrs old) can sometimes sustain itself.

Fish food -> Fish poo -> Ammonia -> Nitrite -> Nitrate -> Nitrogen gas exchanged at water surface