Pond Algae Control
Algae blooms develop when there is an excessive amount of nutrients (such as phosphate and nitrate) in the presence of sunlight. These nutrients come from tap water, rain runoff, fish waste, and debris.
Establishing a self-sustaining pond ecosystem is the first order of business in controlling pond algae.
Rocks and gravel provide the perfect substrate for colonizing bacteria. Bacteria eat nutrients that feed algae, which helps keep water algae-free.
Plants remove nutrients from the water for their own nurishment. Algae compete for the same nutrients. The more the plants use, the less there is for algae to use to grow.
Broad-leafed floating plants such as lilies shade the pond. Algae thrives in sunlight, so adding lots of lilies to the surface will deprive the algae of its sunlight. Read More Here