King British Aquatic Plant Food provides essential nutrients to encourage healthy plant growth. This specially developed formula includes essential nutrients in the form of trace elements required by aquatic plants to encourage healthy growth. As well as adding to the beauty of your aquarium plants, it also helps improve water quality. Plants absorb nitrate (present in the water from fish waste, uneaten food, etc.), so will not encourage unwanted algal growth. Aquatic Plant Food does not contain nitrate or phosphate that would encourage this.