Pond plants are by far the best means of controlling algae, as they reduce three of the four algae stimulants by shading and cooling the pond, and competing for nutrients. Submerged "aerating" plants and floating plants like water hyacinth, water lettuce and parrot's feather are particularly useful, followed by water lilies, and even marginals. * True algicides (Algae Fix, TetraPond Algae Control, Pond Block, Algae Destroyer, All-Clear) actually kill algae directly, but can be harmful to plants, wildlife and possibly pets and children. Dead algae needs to be removed quickly, or it will decompose and foul the water. * Bacteria/enzyme products (Clear Pond, Pond-Zyme, Aqua-Zyme, Ultra Clear) boost the biological breakdown of waste, and are highly recommended when starting up a new pond or biofilter. * Flocculents (AquaRem, Accu-Clear, Crystal Lagoon) help clear cloudy water by causing tiny particles to clump together, making them easier to filter or just settle out.
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