[NoSump]

I have a 72 Gallon tank, with 85 -90 lbs of fully cured live rock. I have no lifestock other than snails and crabs. I only sprinkle a very small amount of Formula One Pellets and a few drops of Micro Vert daily (occasionally every other day) to help sustain my clean-up crew.

Despite the fully cycled live rock, and the low bioload - I have consistent readings of 20PPM of Nitrate. Another factor is that I am using a canister filter (in addition to a Remora HOT skimmer). I had heard that canisters can contribute to nitrates - I recently reduced the biological ceramic rings by half (in the theory that the rock will begin to play the role of biologic filtration.

I have also heard that the filters and sponges can become a source of nitratess? Would it be a good idea to remove everything except the carbon, and continue to run the canister for flow, and some mechanical filtration until my sump is set-up? Thanks.

[zhenya]

Originally Posted by NoSump

I have a 72 Gallon tank, with 85 -90 lbs of fully cured live rock. I have no lifestock other than snails and crabs. I only sprinkle a very small amount of Formula One Pellets and a few drops of Micro Vert daily (occasionally every other day) to help sustain my clean-up crew.

Despite the fully cycled live rock, and the low bioload - I have consistent readings of 20PPM of Nitrate. Another factor is that I am using a canister filter (in addition to a Remora HOT skimmer). I had heard that canisters can contribute to nitrates - I recently reduced the biological ceramic rings by half (in the theory that the rock will begin to play the role of biologic filtration.

I have also heard that the filters and sponges can become a source of nitratess? Would it be a good idea to remove everything except the carbon, and continue to run the canister for flow, and some mechanical filtration until my sump is set-up? Thanks.

Chuck,

I think it would be prudent to remove all of the bio-media from the canister filter and let your live rock and/or sand bed do its job. Same goes for the sponges, if they are not cleaned constantly and allowed to accumulate stuff on them you'll be fighting a loosing battle. I've been there myself when I set up my first tank about seven years ago, wet/dry and all those "wonderful" sponges everywhere. After I removed everything, including the sponges, I saw my NO3 levels gradually drop to undetectable levels by any of the hobbyist kits. After you remove that media, slowly, you should stay on top of the water changes closely monitoring NO3. Are you using RO/DI water?
Lastly, your skimmer alone for mechanical filtration should be fine even without the sump. Make sure it is tuned properly to remove as much waste as possible.
I think in your case the canister filter is the culprit.

[NoSump]

Thanks Gene,

I had a feeling that the canister was the root of the problem. I am using R/O water (but without a D/I).

I'm going to shut the canister down for a few days,and see what happens to my levels. I also plan to add lifestock very slowly. Thanks agin.

Chuck

[tatuvaaj]

One good way to get constantly low NO3 is to put DSB in to the tank. I do understand that not all hobbyists want to have DSB but it will lower your nitrates.

[charlie]

If you don't want a sand bed in your display, you could also do a fuge with a dsb.

[zhenya]

Originally Posted by NoSump

Thanks Gene,

I had a feeling that the canister was the root of the problem. I am using R/O water (but without a D/I).

I'm going to shut the canister down for a few days,and see what happens to my levels. I also plan to add lifestock very slowly. Thanks agin.

Chuck

Chuck, I would rather take the media out and continue to run your filter as an added bonus for circulation or just add a bit of GAC in there. Shutting it down for a few days and then restarting may present more problems,I think, due to the fact that whatever is in that filter will stagnate and when you turn it back on everything is released into the tank. Just a word of caution.
I also agree with other posters that having refugium or properly constructed DSB in the main tank helps bringing NO3 levels to virtually 0( well, there is never true zero in the tank but very close to it).
You can check out our RHO and go through Anthony Calfo's articles and also this month Steven Pro's article that discuss various tyoes of refugia.
http://www.reefland.com/rho/index.php?

[NoSump]

Thank for the helpful advice. I do have a DSB (3-4"), although it probably hasn't yet reached it's full nitrate reduction capabilities yet.

Also, I agree that it will be a better idea to run the canister with carbon only.

Chuck

[tatuvaaj]

Originally Posted by NoSump

Thank for the helpful advice. I do have a DSB (3-4"), although it probably hasn't yet reached it's full nitrate reduction capabilities yet.

That is probably it, yes. Denitrification bacteria take much long to grow and multiply than most aerobic bacteria. (Another good reason why you shouldn't disturb the sand too much).