Quote Originally Posted by reptileszz View Post
I cannot shake these persistant nitrate problems. I have the same problem in both the frog tank and the cory cat tank. I have lost 3 cories so far. All the other parameters are fine. The frogs dont seem to care so far and are growing (and have also stayed in the tank, at least I am doing something right there!)

I dont understand why I have this issue all the time. I do water changes as prescribed, using the seachem prime.

I know there is nothing to do but water changes but with a 10 gallon tank I can only do so much or the water will be all new all the time.

Thanks for listening.
Carole
Are you testing right after using Prime? It tends to skew readings when you do. What are your Nitrate readings? What are the readings from tap? If you have Municipal water I would get a water quality report, seriously.

Here's what I would try:
1. Take your water to a LFS 24 hours after a water change to have them test.
2. Clean filter media in old tank water (swish it around in the bucket you are using to change the water). Old media can become a Nitrate factory if not cleaned properly, but do preserve the bacteria of course which is why you rinse it thoroughly in OLD tank water.
3. If Nitrates still persist start mixing tap with RO (Reverse Osmosis) water to try to reduce the Nitrates.
4. Make sure all food is REMOVED from the tank if not eaten. This is probably the #1 cause of high Nitrates besides lack of maintenance.

African clawed frogs are pretty tough, I think they can handle 40ppm Nitrate just fine. So I would not panic but I would try to get it down to 20ppm for the long haul. Corydora are a bit more sensitive though and three deaths does sound alarming.

Do you know anyone around you who also keeps fish? Do they have the same issues you do? Because if your water is high in Nitrate so is there's.