If you want a natural way get some otocinclus. They are a very small type of catfish and they are great at eating algae, just make sure you have a lot of it when you introduce them to the tank or they may die because they rarely eat on their journey from the wild until they are sold. The cleaned my 6 gallon with everything coated with a lyer of algae in about 4 days. Then all the need is some sinking algae waifers.
