Since 1958

Call Us
(732)462-5005

How to Kill Algae in Your Swimming Pool

Your local pool company can help you determine what kind of algae you have.
Green Algae – is the most common type of algae. It floats on the water and coats pool surfaces. If left untreated, it will turn your pool water pea green.
First, bring into your local pool company with a water sample to make sure it isn’t a mineral (copper or iron) related issue. Second, use 5 gallons of liquid shock per 10,000 gallons of water. It is imperative that you brush the pool surface (walls and bottom) to kick up algae into the water. This enables the shock to work more effectively. Run your filter 24/7 until the water clears. Keep in mid that green or cloudy water can quickly clog your filter and you will need to backwash many times each day. After your water is clear, vacuum up dead algae that has fallen to the bottom of the pool. Use an algaecide to help prevent its return.
Mustard Algae – settles on pool walls and leaves a yellow slimy film.
Use 1 quart of Banish per 20,000 gallons of water plus triple shock pool at the same time (10 gallons of liquid shock per 10,000 gallons of water). After Banish has time to work, brush pool surface and vacuum. Repeat if necessary. Wash all bathing suits. All items that were in the pool must be thoroughly cleaned (rope-n-float, skimmer, baskets, vacuum head and hose). Then carefully place all these items into the shallow end of the pool without ripping liner, add Yellow Out and allow to soak for 2 hours.
Black Algae looks like small clumps attached to corners, steps, pool surfaces or grout if you have tile. Chemically treat pool the same as with green algae, but this type of algae is more difficult to kill. Be diligent in brushing so that outer shell of algae is broken to effectively treat problem. To do spot treatments, turn off the pool circulation temporarily and either pour granular chlorine or rub a chlorine tablet over recently brushed areas. Use and algaecide specifically made for black algae.
Tip for Sand Filters: Add 1-2 lbs. of DE powder into your skimmer when is running. The powder will coat the sand in your filter for extra filtering.

Scroll to Top