It just wont go down!

BarrySpang

Hi everyone, havent been around for a very long time now.

Right, I have a nitrate problem and its driving me mad. Its been up at 100mg/l for a month or two now and ive been doing 20% water changes, I clean the gravel everytime, cleaned all the plants (use plastic ones) and introduced new carbon cartridges, sponge pads and even now cermic noodles (not all at the same time obviously) and nothing seems to be working. All other levels of Nitrite etc are perfect.

I have a 36 gallon tank, about 3ft wide.
I have 4 Yellow Rainbowfish, 1 Swordtail, 1 Dwarf Gourami, 2 Serpae Tetras and a Head and Tail light tetra.
I know some are meant to be kept in groups and I have had them in groups at different stages but due to death have lost a fair few. I have had the tank for 2 years.

Anyone got any ideas?

Cheers.

SolaceTiger

Try shaking your nitrate bottles, sometimes they tend to get "stuck" ... unless are you using test strips? If you are, get a liquid test kit instead. Also, you may wanna check the expiration dates.

daisycutter

i agree with tiger i had a test kit that was retuning 0 nitrate readings on all tanks it may be worth getting a new nitrate test kit
water changes should have made a difference to the readings
the other thing would be to test the tap water a few months ago my tap water started to have high nitrate levels for a short while(2 weeks)

jeaninel

You need to do larger than 20% change. But at that high a nitrate level you don't want to do one huge water change and shock your fish. You'll need to build up to a higher percentage. Try about a 30% change then a few days later do 40%, etc until the nitrates are at an acceptable level (40ppm or less). Then each week test your water for nitrates before a water change and do a large enough change that will keep your nitrates in check each week. 20% might not have been enough of a change for the stock in your tank. On my 55 gallon I do about 40-50% each week and on the 37 gallon about 30%. This keeps my nitrates on both tanks under 20ppm.

Also, as daisycutter suggested test your tap water for nitrates. That may be contributing to the problem.

How often were you doing water changes and how much?

BarrySpang

In answer to jeaninel, I was/am cleaning them at once a week.

One of my rainbows gills is protruding from its head, one of them looks like it has fin rot and another looks like it has flukes.

The gourami has died since I last posted; It had a hole in the head. If i cant treat the fish, what are my options? Is it worht taking them out so they dont infect others or just leave them in and let them die when they are ready.