View Full Version : Removed sandbed, NO3 issues

07/01/2006, 07:26 PM
I've recently made some MAJOR changes to my 65g and now I've run into a problem. I know how it happened... now I need help fixing it!

The tank was a FOWLR with a 2"-3" sandbed, and to make a long story shorter I removed the sandbed, added 35lbs of rock and a bunch of corals from another tank and made it into a reef. Now I'm having nitrate issues, I assume because although the sandbed was disgustingly dirty it was probably doing a fair bit of denitrification.

The tank contains:
100lbs of live rock
LPS and soft corals
8 small fish (Lubbock's wrasse, yellow clown goby, South Seas damsel, Talbot's damsel, white-tail pygmy angel, neon dottyback, 2" flame angel, 2.5" flagfin angel)
2 skunk cleaner shrimp, a few hermits, snails, and an urchin

Levels today weren't great, to say the least, but the tank looks just fine. PO4 0.25 - 0.5 (hard to say, it's a lousy test kit), NH3 0, NO2 0.1 (just barely registers), NO3 20ppm (!!!), pH 8.0.

I'm planning on a large water change tomorrow, and will continue changing water until the levels are better, but I want a long-term solution. Here's what's probably the major issue -- there's a canister filter on this tank, with 4 sponges (2 coarse, 2 fine) and biomedia. The stand doesn't have room for a sump, so I'm stuck with the filter, but I guess the time has come to ditch the media. What's the best way to do this?

07/01/2006, 07:36 PM
I would leave things alone and let the rock balance what bacteria you lost when you removed the sandbed. The tank is seeking equalibrium and water changes will prolong this. As long as you stay below 30 leave it be.

This was what Bomber told me to do when I was having NO3 issues on a new setup. After about 2 weeks of not doing water changes, the NO3 dropped to less then 5.

07/01/2006, 07:45 PM
Really? Okay, that's MUCH easier than removing media and doing massive water changes. I never had NO3 issues previously, if the tank can work its way back to that point without me interfering, so much the better. If you've been through it and Bomber gave you advice that worked, I'll certainly go along with that :D

07/01/2006, 07:50 PM
Just be sure to keep them below 30, like I mentioned. Another thing....

What corals are in that tank now? Some corals aren't forgiving of higher NO3.

07/01/2006, 08:22 PM
I agree with Aquaticman, leave it be. I don't know what your photoperiod is, but some extra ligh will help some algaes soak up the trates. Algae is good in your case, once things are under control you can worry about getting rid of the algae.

07/01/2006, 08:43 PM
Thanks for the second & third opinions. I'll keep checking, make sure the nitrates stay at this level and don't rise.

The corals I've got right now are:
yellow polyps
Xenia (hoping this will suck up some nutrients too)
fiji yellow leather

I'm not so worried about the softies, but I'll keep an eye on the LPS. I need to pick up some phosphate remover to bring the PO4 down to ~0 to avoid stressing these guys out too.

The photoperiod is long, 14h total (daylights are on for 12h, actinics an extra hour in the am & pm).
Would Caulerpa be a good idea here? I have some C. verticillata growing in another tank, I could transfer a rock over to the 65g. Then again, the angels might just eat it...