Most household Acrylic and Glass Cleaners contain ammonia or other harsh chemicals that are toxic to fish, reptiles and invertebrates. Fritz Glass & Acrylic Cleaner is ammonia free and safe to use on exterior surfaces around an aquarium or terrarium. The unique streak-free and drip-free formulation helps repel dust, fingerprints and water spots. Also great for electronics, Glass & Acrylic LCD Screens, Silicone & Rubber. Fritz Glass & Acrylic Cleaner also reduces friction when using magnetic scrapers on aquariums.