For ornamental fish and garden ponds. Cleans and controls unsightly debris year round. Contains no toxic algaecides or other harsh chemicals. Completely safe for all plants and fish. Treats 1875 gallons! Every pond is plagued by soupy, murky sludge build-up at one time or another. Not only is this water condition unsightly, but it is also harmful to plants and delicate microbial life by using up precious oxygen and nutrients. Pond Control contains billions of live, beneficial sludge oxydizing bacteria in 5 different strains to provide full-spectrum elimination of excess proteins, uneaten food, fish feces, and organic sludge layers that cause murky water. Plus, Pond Control contains an aqua-culture-grade sun shade that will screen U.V. light without inhibiting your wanted plant growth or turning your pond an odd blue color