Swimming Pool Algae Removal

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Pea green colored water in your swimming pool is not very inviting after a long, hot day working in the yard. The algae that is responsible for the green color to swimming pool water must be destroyed. Adams Pools AC.com says that there are several ways to accomplish this.

Why Algae Develops

Algae grows when chlorine levels get too low, according to Steve Litt, creator of Universal Troubleshooting Process. Litt also says that algae must have water with phosphates in it to grow. The problem is that phosphates are everywhere. According to Litt, if you have swimmers, you have phosphates. Phosphates also develop when organic material, such as leaves and pine needles, break down. Different phosphate removers on the market can help eliminate phosphates from your pool.

Brush Walls And Floor

The first step to removing algae from your pool is to brush all of the walls and the floor, according to Merchant Circle.com. This will remove any algae that has grown on those surfaces and make it easier to kill with any of the treatment methods that follow. The goal with this is to remove as much of the algae from the walls and floor as possible.

Chlorine Shock

Chlorine shock is one way to kill algae in a chlorinated pool. The normal dose of chlorine in a pool is 1 lb. of chlorine for every 10,000 gallons of water. To do a chlorine shock, Merchant Circle.com says to use a dose of 1 lb. of chlorine for every 7,500 gallons of water. It is important to dissolve the chlorine shock in a large bucket of water before adding it to the pool, and the filter system should run 24 hours a day during this process. It is safe to use the pool again when the chlorine levels return to the recommended level of 1 to 3 parts per million.


Metallic or quaternary ammonia algaecides are also an effective way to kill algae in a pool, according to Adams Pools. Which ever kind you decide to use, it should contain at least 30 percent of the active ingredient. You should wait at least one day after applying according to manufacturer's directions before using your pool again. There are a couple of benefits to using algaecides. You can use less chlorine, which means more comfortable swimming and they also prolong the life of your filter system, says Adams Pools.

Double Dose

The most effective method, according to Adams Pools, is a combination of algaecides and chlorine shock. When using this method, you should use the algaecide first so that the chlorine won't keep the algaecide from working. Once you have completed these treatments, you should vacuum the algae up and clean your filters so that you don't give the algae a foothold to bloom again.