Dennerle Aquarium Starter Rapid is a highly effective product for a rapid, safe start for newly established aquaria. It is made up of two components:1. Living filter bacteria - they settle on filter material and gravel and instantly begin breaking down pollutants. The bacteria solution is highly concentrated, with a guaranteed 500 million bacteria per millilitre (when filled).2. Bacteria booster nutrient solution - the specially developed bacteria food ensures rapid growth and reproduction.Powerful nitrification bacteria (Nitrosomonas, Nitrobacter) convert harmful ammonia into nitrate via nitrite, detoxifying the water. In the anaerobic areas of the aquarium - primarily in the substrate and the filter - denitrifying bacteria (Paracoccus) convert nitrate into gaseous nitrogen, reducing the nitrate content. The filter bacteria also break down dead plant matter and food residues, fish excrement, organic impurities, proteins, fats, carbohydrates, harmful organic substances and organic slud