Getting rid of algae

Q. My small aquatic garden is beautiful, but there is too much algae on the water surface. How do I get rid of it?

A. A small amount of algae in water gardens is a natural occurrence. A large buildup, however, can detract from the beauty of your garden and should be "managed" in any of the following ways. If your pond is in full sun, be sure water plants shade the water surface since algae thrives in full sun. If fish are fed too frequently, their uneaten food will encourage algae. If your pond contains too many fish for the volume of water, you will probably need a pumped filtration system.

A brand new pond often goes through a settling out period (during which algae can appear) before a proper balance is achieved among plants, fish and scavengers. Be sure your pond contains enough plants for its size, particularly the submerged aquatics known as oxygenators. They absorb nitrates from the water, thus depriving algae of their food source. Any chemical algicide (as long as it is harmless to fish) can do a temporary job of keeping algae at bay, but it should not be viewed as a long-term solution.