No test kit, we take samples to the store to be tested. I guess because we have never had a problem at all with our tank we just never got a test kit. How often do you test your water at home? We are taking samples once a month, but twice in the last three weeks. I will transfer the pleco tonight. I just never dreamed it could be one of his tankmates since they have all gotten along for so long. By the way the catfish is not a synodontis catfish.