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How to Clear Black Algae from Your Pool

Black algae is an aggressive infestation of your swimming pool that can’t easily be eliminated with normal swimming pool chemistry. It appears as small spores on the walls or bottom of the pool. The trouble is, black algae blooms are stubborn and won’t die when you shock your pool, even if you add algaecide. The roots anchor into small cracks in the pool surfaces and develop a waxy protective barrier, which makes black algae hard to kill off. If you have black algae blooms in your pool, follow these steps to get your pool back to normal:

Step 1: Sanitize

Black algae is not directly harmful, but it can harbour dangerous organisms like E. coli, so it’s very important that you sanitize everything. Wash bathing suits and sanitize all pool equipment and toys. Wear gloves and use a brush to scrub at the surface of these objects, then rinse clean with water.

Step 2: Test Your Water

Your pH levels should be between 7.4 and 7.6, and the alkalinity levels should be between 120-150 ppm. Bring a sample of your water into the Purewater store and we’d be happy to test it for you and set you up with products to get your water properly balanced.

Step 3: Brushing

This is an essential step, because you need to disrupt the protective barrier so the chlorine can reach the black algae directly. Aggressively brush the walls and steps of your pool and attack those black algae spots. Attach the brush to a pool pole to reach the lower portion of the walls and the pool bottom. Remember, black algae is stubborn, so you need to be thorough.

Step 4: Shock Your Pool

If you have a strong case of black algae, you’ll want to double or even triple your dosage of shock. Keep your filter running 24 hours per day until the black algae has cleared.

Step 5: Brush Again

You didn’t think we were joking about how much you need to brush, did you? Brush your pool thoroughly multiple times per day. Each time, you’re getting closer and close to making the roots vulnerable to the chlorine, so keep at it.

Repeat Steps 2-5

You need to be aggressive to match. Just keep at it. If the problem isn’t clear or if you need more assistance, give us a call or come into the Purewater store. We’d be happy to help clear up the problem so you can enjoy clean and clear water in your swimming pool once more. The best solution is always preventative measures, so talk to us about arranging scheduled maintenance services for your pool to prevent black algae from cropping up again.

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