The Acurel F25 Millimeter Water Clarifier is a simple and effective way to keep your aquarium water clean and clear. With a 25 millimeter liquid volume and 0.6 pound item weight, it is one of the best options for keeping your fish healthy and happy. The Acurel F25 Millimeter Water Clarifier is made of safe and natural ingredients that are easy on your fish’s health. It also treats up to 250 gallons of water per day so you don’t have to worry about your water getting too dirty.