SeaChem Flourish Excel - 250 ml is designed to support clean, balanced aquarium water. Flourish Excel is a simple source of carbon for aiding growth of aquatic plants. Designed to make plant-keeping easier without carbon dioxide injection. Use it alone, or if you choose, with carbon dioxide injection. Keeps iron in a reduced state that's easily utilized by plants. 1 ml treats 10 gallons. Recommended for use on a daily to every other day basis. Shop SeaChem aquarium water conditioners at Uncle Bill's Pet Centers for trusted pet supplies and knowledgeable service in Indiana.