Causes of algae and how to get rid of it

Although swimming pool maintenance is not difficult things can sometimes go wrong. Algae can appear suddenly and grow even though you maintain your water on a regular basis. Different types of algae can cause a variety of symptoms in your pool water. If you're wondering why there is so much algae in your pool, re-examine how often people use the pool along with other conditions that can cause a change in water chemistry.

Several types of algae commonly cause problems in swimming pool water. Green algae is the most common. It can show up suddenly when temperatures are warm and pools are frequently in use. It is one of the easiest pool algae problems to treat. Black algae is the curse of swimming pool owners. It has a hard, shell-like coating that sticks to pool surfaces and must be vigorously scrubbed to be removed. Yellow algae is also difficult to remove but can be eliminated with treatment. Pink or red algae is not really an algae but a fungus called Paecilomyces lilacinus that can cause a slimy pink or gray film in your pool.

Even if you maintain your pool water carefully, algae problems can develop when the algae spores are carried into your pool by the rain, the wind or by contaminated bathing suits. Intense sunlight, hot weather and the presence of nitrates in the pool can make conditions perfect for algae growth. Algae not only makes pool water unpleasant, it can clog pool filters and cause more bacterial growth in the water. It also increases the need for more chlorine in your pool.

To remove algae from your swimming pool first shock the water using 10 times the amount of chlorine that you ordinary use. This should be about 10 parts per million of free chlorine. Run your pool filter for at least 24 hours to allow the chlorine to circulate through the water. Use a pool brush to remove the algae from the pool walls and floor, and vacuum pool surfaces. Add a commercial pool algaecide to help kill the algae quickly. Continue running the filter until the water is clear. You may need to brush the walls of the pool for several consecutive days to remove all the algae. Retest the pool water and adjust the pH with muriatic acid or sodium carbonate if required.

To prevent the growth of algae in your swimming pool, maintain the proper water chemistry on a weekly basis in hot weather. Ensure that your filtration system is in good working order. Brush the walls and floor of the pool and vacuum weekly. Use a solar blanket to keep debris out of the pool and rinse out bathing suits after use to prevent recontamination.