The Pond Digger Brand Cold Tempeature Beneficial Bacteria is a specially formulated bacteria blend to support healthy fish and pristine water quality on ponds and waterscapes with water temperatures ranging from 40-60 degrees. This premium quality blend of electrolytes, enzymes, and pro-biotic microbes consume build-up and sludge, uneaten fish food, fish waste, and other organic debris — all of which if unchecked can affect pond clarity, water quality, and even fish health. This concentrated water treatment is completely dissolvable to produce the best results in your pond or water garden and contains more than 1 billion colony-forming units in each gram! Use 1 teaspoon (approx. 1/5 oz) per 1000 gallons, recommended for weekly maintenance.