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How To Get and Keep Algae Out Of Your Salt Water Pool

Treating Algae in Salt Water Pool Canada Have algae growing in your salt water swimming pool?  No worries, like a regular chlorine swimming pool, getting rid of algae isn't hard. Even though some swimming pools run on salt water they still depend on chlorine. This is because the salt is filtered by an electrically-charged line and is then converted into chlorine. You’re still swimming in a chlorine-based pool, but the way the chemical is added is slightly different. Chlorine can and should still be added to a salt water pool each week to shock it. Most salt water models have an option that enables you to super chlorinate the water, but this isn’t a strong enough way to oxidize the pool and that’s why a weekly chlorine shock is still needed. That being said, you should also engage the salt water system’s super chlorination option once a month, but be aware that it won’t be strong enough to rid the pool of algae. The best way to eliminate algae is by simply using a conventional chlorine shock. By following the steps below you should be able to keep algae in control in your pool.

1-Brush the pool

It’s recommended that you brush the walls and floor of the pool before shocking it. You’ll find that algae forms and clings to the sides and bottom of the pool and it’s easier for the shock to destroy it if it is drifting in the water. Don’t forget to brush the hard-to-reach areas behind the pool steps and ladders etc.

2-Shocking a salt water pool

Before shocking a salt water pool you should test the water with a test strip or take a sample of it to a pool shop. The alkalinity and pH levels need to be correct, meaning the alkalinity should be between 120 parts per million (ppm) and 150 ppm and the pH should read between 7.4 and 7.6. If the water is properly balanced the chlorine shock will be more effective. If the water appears to be a teal colour or light green due to the algae then you should give the pool a double dose of a calcium hypochlorite shock. If the water looks dark green then a triple helping should be used and if it appears to be black then a quadruple shock is best. In general, one pound of shock should be enough to treat 10,000 gallons of pool water. If you’re giving it a double dose of shock you’ll need two pounds per 10,000 gallons with three pounds needed for a triple dose and four pounds for the quadruple option. It’s also more effective if the shock is added to the water at dusk when the sun has gone down or later. The pump and filter should then run for a minimum of eight hours so the shock can circulate through the water and eliminate the algae. After the shock has been added to the pool the water should be a cloudy blue colour.

3-Run the filter

The dead algae will make the water appear cloudy, but it should soon clear up when the water goes through the filter. At this point the filter should operate 24 hours a day to clear the pool. You may also want to speed things up by adding water clarifier. It’s safe to enter the pool in the cloudy water and the movement of people in it will also assist the filter as it gets rid of the algae particles. If the water colour still appears to be teal or green you should repeat the process and shock the pool again. Since pool owners rely on shock to keep their water clean throughout the swimming season it’s a good idea to buy it in bulk to save on costs. If you buy it in bulk you’ll also have some on hand when it’s needed.

4-Keep the water properly balanced

If you simply can’t clear the water and it stays cloudy you will need to make sure the water is properly balanced and you may want to take it to a pool shop at this stage. It’s important that the water chemistry is always properly sanitized and balanced to keep algae at bay and to run the filter for a minimum of eight to 12 hours each day.

5-Regular maintenance

You can also help fight off algae by brushing and vacuuming the salt water pool on a regular basis and shocking it once every week. Algae can also form on pool covers, toys, accessories and equipment so it’s recommended that you also pay attention to these items when cleaning. Have questions about what chemicals to use when shocking your salt water swimming pool?  Contact the pool experts at, we Canada's leader in online pool supplies.  We offer fast and free shipping across Canada and prices lower than your local pool store.

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