Nitrate problem?

[samsreef]

I think my Dad's 400l tank (about 100 US GAL) has a serious nitrate problem (well I hope its not nitrite or ammonia). The tank is heavily overstocked (I'm going to be moving some of the fish in to my 65gal) and he has an external fluval 404 canister filter & an internal filter with sponges and stuff.

I have told him he needs to get a sump/refugium and he needs to clean the filters more regularly (he only cleans them once a month, I just removed two layers of pre-filter floss from the internal, they used to be white and they head a lot more muck on them than the protein skimmer had took out...).

The protein skimmer is pretty good, aqua medic turbo floater.

The main problem I think is that he has a fluavised bed filter (he was advised to get one from the shop when we were setting it up, it was called "essential"). I have heard they are no good for a reef because they generate a lot of nitrate.

The other two problems are that he doesn't hardly any live rock (about two pieces, the rest is ocean rock) and the only circulation is from the filters (I just gave him a 802 US GAL pump to try and help a little).

He didn't listen to me but now he wants to know what's happening because all of his corals are dying (he gave me a brain coral, what's left of it, to try and save it).

I think he has a nitrate problem, what do you think?
Should we remove the fluavised bed filter?
Should we add more live rock or will this start another cycle? (remember he has a heavy bio load)

Look forward to hearing your much valued comments & suggestions, we are both really upset because he has spent so much money on the tank, it's been running for a year now.

(P.S I can't be certain that it is a nitrate problem, but the water is really dirty, lots of detritus because of no circulation. He doesn't believe in test kits but I'm going to do a nitrate, ammonia and nitrite test when I can get him out the way)

[Samper]

First I'd test but if it's heavily overstocked then nitrates very well could be your problem. With regular water changes to include vacuuming and a good skimmer you should be able to keep things under control without all the other equipment. If you guys aren't testing your water parameters then maybe you should be just to help you learn your system a little better. More flow will also help you keep particles in suspension longer so that your skimmer can remove them.

[samsreef]

Thanks for the info, I'm going to test tomorrow and then we will do a water change. Once we get a bit more flow in do you think it will be safe to remove the fluadised bed filter?