TLC Marine SAT Biological Clarifier, 32 oz For reef tanks and saltwater aquariums. Use TLC Marine SAT Biological Clarifier in problem tanks only, whenever water clarity needs improvement. Apply whenever problems arise and repeat weekly. Use 2 ounces for every 25 gallons until the problem is solved Tank and rock surfaces will be cleaned, and water quality improved, in one to four doses. Longer term or more severe problems take longer to solv