Nitrates too high

Right now my 90G tank has about 40 ppm nitrates and I'm having a hard time getting them down. I did three 20% water changes last week and treated the water with natrual nitrate reducer/remover. Still nitrates are way too high to add new fish. Right now the only fish that are still in the tank are chromies, one damsel, marine beta, watchman, and dragnet. We have lost several clown fish because of either a sickness or the high nitrates.

Would this be a result or over feeding? Not enough micro algae? Not enough water changes?

I ordered a reef octopus skimmer and it should be here tomorrow. And my chaeto is about the size of two soft balls. Also 5 mangroves growing with lots of roots.

What else should I be doing to keep the nitrates down?
Thanks

 

Are you sure your test kits are accurate? I would suggest you try another test kit first. 40ppm nitrates should not kill a fish.

 

Ya, we tested it and thought it wasn't bad. Took it to the LFS to have the works tested and they said too high of nitrates. I'm pretty sure they measured 40ppm and said not to buy the two skunk clowns we wanted because they would probably not do well at this point.

It kind of makes sense, though. We were having a hard time keeping clown fish alive and they would live for 2 months and slowly die. It looked like they had ich, but none of the other fish got sick. Just the clown fish. Started with the black percs then killed 3 maroon clowns. If it wasn't ich that killed them, or high nitrates, maybe clown fish disease? We just want to get the nitrates lowered a little so we can try a couple more clows again.

Would it be ok to get two clown fish with 40ppm nitrates?

Like I said, the skimmer will be here tomorrow, and I added more chaeto last week.

 

I'd get the skimmer on and fine-tuned, then let it run a few days before adding anything. Also, are you using RO/DI water? If not, you just may be putting nitrates back into your tank when you do water changes.

 

I suspect over feeding is a contributing factor. The fish would probably do ok, but I would not add anything to the tank at this time until the nitrates do come down.
Telling the difference between Marine Ich and Brookynella is pretty easy. Brookynella appears as a white coating covering the fish, slimy in appearence. Marine Ich looks like grains of salt initially. Brookynella kills quickly as well. The spots of Marine Ich may fade and reappear during the photoperiod and after consecutive days in a row as the disease goes through it's life cycle.
If either disease is present in your system the fish are going to be at a greater risk because of the elevated nitrates. Get the nitrates down first and then the fish IMO.

 

use RO/DI water; trust me, because me using tap water has given me really high nitrates even after doing 2 20% water changes in one day, and I also got algae in all colors of the rainbow lol

 

agreed....keep battling those nitrates before adding more fish...feed less and make sure there are no nitrates in your replacement water for water changes. The 40ppm may cause stress to a fish, then the fish would be more susceptible to ICH, may be what has happened.