Review on ACCU-CLEAR Water Clarifier for Freshwater Aquariums - Quickly Clears Cloudy Water, Ideal for Weekly Use by Ashley Ellis

Used them on my 55 gallon tank as intended. Had one dose and another 24 hours later. The fish were gasping at the top of the tank and my catfish swam almost dead across the tank. I did an emergency water change and was able to save her. It did not affect the clarity of the water in any way and I am convinced it is toxic to the fish. I have used Tetra Water Clarifier in the past and have never had a problem. I have requested a refund for this Revain product.