Nitrates

[Captain Jack]

I have a 30 gallon tank, which I pretty faithfully done weekly 10% water changes; but I keep getting nitrates in the 20-ish range when i want them in the <5 range.

Any suggestions? maybe someone with a similar tank size will have some insight on this.

Stats:
Life: pair of o.clowns, neon-goby, bi-color blenny. skunk cleaner shrimp. 4 peppermint shrimp (got rid of the aptasia ). large feather duster, some xenia, 1 mushroom, and 1 Kenya tree; some cheato in the fuge.

Stuff: lots of live rock (not a clue on the weight, but as much as i can fit and still have swimming room for fishes), 4+ inch DSB, hang-on skimmer, hang-on refugium (small), eheim classic canister.

Basicaly I'm thinking to feed less and maybe take the bio stuff out of the canister filter. but i was curious if anyone else had insight.

[ErikH]

First, clean your canister.
Try taking the rock out and setting it in buckets after shaking them off in the water.
Then, swirl the water around in the tank and get as much detritus suspended as you can and do a large water change.
Replace the rock and let the canister remove the rest of the detritus from the water column.
Clean the canister again, and retest.

But, before you do all of that, take your water to be tested at the LFS.

[Ping]

What kind of skimmer and how often does the cup need cleaning?

How often do you clean the canister?

How much flow?

[rz1a]

whats the reason for wanting it so low? do you have nuisance algae or any corals that are sensitive to nitrates?

[Captain Jack]

I want the nitrates low mostly so I can have things healthy for my existing corals and also be able to try out other corals in the coming months. Even though I'll probably stick with softies for some months to come, the current 20 ppm seems high for recommended coral keeping.

Water flow is as high as I can get it without blasting away my softies and feather duster. Two koralia 1's at 400gph each (which is alot in 30 gallon tank), and canister filter (up to 66 gal tanks) at about 116 pgh, and hob skimmer and hob refuge.

The canister filter was about 6-7 weeks old and hadn't been cleaned, so I cleaned it out over the weekend. Didn't seem very dirty and not clogged up.

My skimmer is aqua-c remora, rated up to 75 gal tanks. I empty and clean the cup a couple times a week. There will usualy be less than 2 inches collected in the cup (weakish tea colored i guess, i don't drink tea), but the neck gets gunky so that's why I clean it out more frequently.

Thanks to Ace, I've added some more macro algea, so that can help with nitrogen export. It just seems that perhaps because my small tank size with 4 fishes, nitrates are always staying around 20 ppm; even with weekly water change. The large clown (and cleaner shrimp) is very agressive feeder, so I try to feed enough the that bi-color blenny and neon gobie still get a few bites.

So I'll watch a few more weeks. continuing regular maintenance, cleaning the canister monthly, feeding somewhat less; and see if things improve. Spending lots of money is not something I would like to do, so that rules out larger skimmer, installing RODI unit, nitrate reactor, etc.

[Captain Jack]

Maybe in a year or so (after light upgrade, and some more experience), I can try getting a small-giant clam for my 30 gallon. That might help filtration as well.

[tony]

two koralia 1s arent really a lot of flow for a 30, i have 2 #3s in my 30 cube

i would ditch the canister filter and get a good or better skimmer. i do 5 gallon water changes monthly/bi-monthly and have never had nitrates over 10 and im fairly heavily stocked

[Captain Jack]

2 koralia 1's is 800 gph. that should turn over the volume of the tank 27 times an hour (over 30 times if you count canister, which DOES put out a good current). Anyway, I had a hard enough time finding a combination of diretions to point the powerheads and didn't make my feather duster and sofities hide all the time from being battered by the strong current. it's a 30 long, maybe that makes a difference.

And since I'm on the slow (low budget) salt water hobbie track, it will be several months before I can buy the lighting upgrade I want. Maybe sometime after that I can consider another upgrade on skimmer, though I thought mine was good as far as HOT goes. And Sump would be too much trouble for now. That or save up for RODI, or any other number of nice-to-haves.

[SABOB]

Are you using tap water or buying water from LFS?I see where you can't afford a RODI of your own but wondering on what type water you use for ater changes?

[Captain Jack]

I'm using tap water. I mix up several weeks worth at once, and then age it at least a week. I understand that should be sufficient for chlorine to escape, though I imagine there's still phosphates (and other things) and possibly nitrates. I'll make it a point to test the "new" water for nitrates next time.