Phosphates in Swimming Pools Causes Effects and Treatment

Phosphates Overview

If you have noticed that your swimming pool is prone to algae buildup, you are not alone. The source article describes algae blooms as a fairly common pool maintenance issue. According to the source, addressing algae after it appears may not get to the root of the problem, and phosphates in the pool water can contribute to the green or cloudy water that algae can produce.

What Are Phosphates?

The source article describes phosphates as a type of organic compound found in many common products. They can enter a swimming pool from a number of sources. According to the source, makeup, hair products, and lotion that swimmers wear can rinse off into the pool water, leaving phosphates behind. Twigs, leaves, and bark may also blow into the pool and produce phosphates as they break down. The source notes that runoff from sprinklers can also carry phosphates from lawn fertilizer into the pool.

The source article notes that limiting these sources can help, but completely preventing phosphates from entering the water can be difficult.

How Phosphates Affect Pool Water

According to the source article, phosphates can be a food source for some types of aquatic plant life, including algae. When the phosphate level in a swimming pool gets high, the algae population may also increase. The source describes some signs of high algae that homeowners may notice, such as cloudy or green water, green or mustard-colored debris on the water’s surface, or a slimy film on pool surfaces. The source also notes that you may need to use more chemicals to treat the pool water when algae is active.

How Phosphates May Be Treated

The source article notes that before treating phosphates, an accurate measurement of phosphate levels in the pool water is needed. The source describes commercially available test kits as one way homeowners can check phosphate levels. Once levels are known, the source article describes using an appropriate phosphate remover to help bring the phosphate concentration into a reasonable range.

If you choose to use a phosphate remover, follow the product label directions or guidance from a pool service professional, including any directions about pool filter operation before and after treatment. The source article also notes that periodically checking phosphate levels can help homeowners decide whether a repeat treatment may be needed.