Question: What are Phosphates?
Answer: Phosphates are a type of nutrient necessary for the growth of algae. During the 1960s and ‘70s, America had a serious problem with eutrophication of its lakes and streams. Basically, many of our lakes and streams were becoming clogged with algae. Many expensive studies were done to determine the cause of this and they found that elevated levels of phosphates in the water allowed excessive amounts of algae to grow. The studies showed that algae growth is limited by the amount of phosphates present in the water.
Algae is very much like a plant and blows into your swimming pool as spores in the wind. While chlorine will often prevent algae from blooming, it does not always work and 60% of swimming pools typically experience strong algae growth at least twice each year. Killing the algae requires using very high levels of chlorine and algaecides. The dead algae are typically collected in the pool filter which slows the flow of water through the pool and may require the filter to be cleaned.
The solution for this problem is to remove the phosphates from the water before the algae can develop. Phosphates enter the pool through fill water, decaying plant matter, poorly-spread fertilizers, dust/dirt, rain water and some common pool chemicals. Each pool is different, but it is normal for a pool to acquire 200 parts per billion of phosphates during the course of a year. If the phosphates are not removed on a regular basis, they accumulate and allow for algae to take over.
Normally phosphates are liquid and travel though the pool filter. Removing them requires adding expensive phosphate removers. The best phosphate removers are made with lanthanum. Lanthanum bonds with the phosphate present to form a compound (lanthanum phosphate). This compound only lasts for seven to ten days and forms particles large enough to be trapped in the pool filter. A week after adding the phosphate remover, the filter is cleaned and both the lanthanum and phosphates are removed together.
The process can result in some temporary cloudiness of the water before it has been filtered, but is completely safe for swimming.
Penguin Pool Service tests each pool for phosphate levels during the early spring (after most of the winter storms). Performing the phosphate removal process regularly allows your swimming pool to avoid algae blooms and the harsh chemicals required to treat them.