3 Reasons to Routinely Drain Your Swimming Pool

Most swimming pool owners never think to routinely drain a portion of the pool water and refill it with fresh fill water. But as time goes on and as more chemicals and other foreign substances are introduced into the pool, various elements of the pool water change and can move outside acceptable parameters. A number of these changes can lead to recurring problems with algae as well as creating additional expenses trying to deal with the problems.

Dilute Total Dissolved Solids (TDS) - high levels of TDS (total dissolved solids) can interfere with the ability of chlorine to sanitize the pool water. If you're having persistent problems with algae or you're having trouble holding a sufficient chlorine level, have your pool water tested for TDS. If it's too high, partially drain the swimming pool until the TDS reading is at the appropriate level.

Dilute Cyanuric Acid – cyanuric acid is used as a conditioner or stabilizer that protects chlorine from the sun. When stabilized chlorine is used to sanitize the pool, the level of cyanuric acid in the pool will slowly rise over time. The optimum level of Cyanuric Acid in a swimming pool is about 20 – 50 ppm. If the level is below that, the sun will destroy the chlorine at a high rate and more chlorine will be needed. As the level gets over 50 ppm, the chlorine will be over stabilized and lose its ability to sanitize the pool water. It's a good idea to test for cyanuric acid at least once a month. When the level exceeds 50 ppm, dilute the pool water to bring the level back in the proper range.

Dilute Phosphates – Phosphate is an important plant nutrient and when present in a swimming pool can serve as food for algae. The phosphate level in the pool will slowly increase as different foreign substances such as bather wastes, bird droppings, leafs, rain water, and many other substances enter the pool. The ideal level for phosphates is around 125 ppb or lower. When the level gets over 200, algae can begin to grow and thrive. Similar to TDS and Cyanuric Acid, you should have your swimming pool tested for phosphates periodically. As the level approaches or goes over 500 ppb, start planning to dilute the pool water soon in order to bring the reading back down to the 100 – 200 level.

All three of these elements of swimming pool water will slowly increase over time and can lead to real problems. Routine maintenance can quickly turn into one headache after another. A crystal clear swimming pool can quickly turn into a pool with recurring algae problems. Get your pool water tested for Total Dissolved Solids (TDS), Cyanuric Acid, and Phosphates at least a few times a year. And build into your plans for routine pool maintenance draining half your pool every year. Doing so should help keep these issues in control and help keep your job maintaining your swimming pool easy, and help to keep your swimming pool crystal clear throughout the year.

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