Algae growth control is a perplexing problem for maintain pond keepers. Here's what you need to know about Pond Algae Control.
Construction Considerations
Creating a pond of varying depths is best for overall water quality. About forty percent should comprise the deep end, the depth of which will be dictated by the fish and plants you want to keep in there. Thirty percent should be at an intermediate level and the remaining thirty percent can be dedicated to the shallowest end, usually one- to one-and-a-half feet deep. This sloping will make physically removing algae and debris easier. A good pond skimmer will skim out the majority of pond debris and algae. Keep in mind that ponds constructed of concrete, limestone or marble will tend to have higher pH levels, which can discourage algae growth, than those with a plastic liner.
Equipment
Proper filtration will go a long way toward keeping algae growth in check. The filter pump you choose should be capable of re-circulating at least half your pond's volume each hour. If you have a lot of large fish, choose a filter that can handle the entire volume each hour. Keeping the water moving from bottom to top is essential to avoiding stagnation. Vacuuming pond sludge from the bottom is also helpful
Bring Out the Big Guns
If algae overgrowth is a chronic problem in your pond, consider installing an ultraviolet light sterilizing system. Ultra violet light destroys the DNA in single-cell algae and can produce crystal-clear pond water quickly and efficiently.