All fish bowls gradually accumulate fish wastes and uneaten fish food at the bottom of the bowl which reduce oxygen levels and produce toxic gases in the decomposition process. Aqua Master Fish Bowl Cleaner contains a high concentration of selected natural bacterial micro-organisms popularly know as “natures housekeepers”. When added to fish bowl water the micro-organisms use organic waste and nutrients as sources of food  for their own growth, producing harmless carbon dioxide and water as waste products.