I took a sample of water and the dead froggies into Petsmart where they came from and they said that the nitrates were off the charts. I came home and totally cleaned the tank, rinced and rinced the gravel, stones, filter etc. I had been doing quarter water changes every week and I had only had them 18 days what did I do wrong? Is the third likely to die? Yesterday they were barking at me.![]()