Hello all, I'm having issues with two cory catfish, one died three days after I bought it, and the other is on its way out today, nine days after I purchased them. My tank is a twenty high and water parameters are:
Ammonia: 0 ppm
Nitrite: 0 ppm
Nitrate: 5 ppm
pH: 7.8
KH: Between 4 and 5 degrees...