Purpose and Benefits: AlgaeFix is a liquid algae-control product for use in ornamental fishponds, water gardens, fountains, and freshwater aquariums. AlgaeFix is approved for use in ponds and aquariums containing live plants and fish. AlgaeFix controls many types of algae including "green water" blooms and filamentous algae. AlgaeFix is colorless and non-corrosive..