Nitrate levels - Need Help

A few things -

1) how old is the test kit? Some have expiration dates. I like the titration versions - uses drops til the color changes - rather than the simple test strips.

2) Have your water tested at a store.

3) Wet dry filters are notorious for being nitrate sinks. Use a few big, thick pads as a prefilter to avoid having to break down the filter more often.

4) You have a ton of fish in there. You dont mention if they are 2" or 5" long, but either way the metabolic load is pretty high. I would do weekly 50% changes or unload a few fish.

5) Anubias aren't as good at sucking up nitrates as some of the faster growing plants are. Anacharis and java moss are great. You can put them in your sump behind the baffles so the pump wont suck them up, but they will do better with some light. They grow like weeds and as you trim them and remove the growth you remove the nitrates.

Best bet is to scale back the food, increase the water changes.

Sounds like your system is working just as it should.
If you are at 30ppm after your water change you need to do a bigger water change to get to 20ppm. Nitrates go up not down over time. the only reliable way to get rid of them is with a bigger water change.
Yes I know plants are supposed to use nitrates but with 50 fish in the tank you won't be able to fit enough plants to make a dent in your nitrates.
Well,maybe you could but you wouldn't be able to see the fish!

seems in line to me. i dont feel nitrate at 30 ppm is outrageous. you do have about 50 fish in there, which creates alot of waste. i would increase water changes to 50-60% and maybe every once in awhile throw in an extra water change every month, for 5 or 6 changes.

Hello fellow Aquarist,

Ok, i need to understand if i have a problem or not. I am trying to understand what I can do to bring my Nitrate levels to at least 20PPM. Little history of the tank first - Started the tank on the last week of June 2012. It’s a 150G tank with Eco Complete Planted Black Aquarium Substrate, Wet Dry Filter that uses a GlassHolz 3000 overflow box, a 1500gph circulation pump to keep circulation at the bottom and a Supreme Classic Mag Drive 1800 Pump in the wet dry tank.

This tank is also planted with about 12 assorted Anubis. As for fish, I added them 3 weeks into the fishless cycle. I have 44 African Cichlids from Malawi & Tanganyika lakes and about 3 catfish and 3 algae eaters in total. The Temp runs at 76 to 78F. My Ammonia and Nitrite are zero, pH is at 8.2 but my Nitrates are 30ppm after a fresh water change of 30 to 40%. At the end of a week (after the water change) its back to 40 to 50ppm and it is driving me nuts.
Last week I cleaned out the Wet Dry Filter and mechanical media (the Bio Balls) to get all the food that was stuck on the bio balls off and when I put everything back together again, the Nitrate was still high – 30PPM. I tested my house tap, the Nitrate was zero… I was very guilty of over feeding initially but have curbed it back a bunch, so now I need to know after doing the deep clean, plants and weekly water changes, what more do I need to do to get these nitrates in check? Or do I not really have a problem at all?