How to Kill Black Algae
- 1). Brush the algae with pumice stones to tear through the algae's protective layers. Another effective tool, according to PoolCenter.com, is a trichlor tablet or stick. Black algae, in particular, develop layer upon layer of protective coatings that make their removal impossible if the layers on the head aren't broken.
- 2). Change the filter to allow for maximum filtration. Vacuum up the heads and back-wash them out of the filter as soon as possible.
- 3). Run the filtration system for 24 hours. If the pool doesn't clear, brush it again. Continue to brush until the algae are no longer noticeable. This could take several days.
- 4). Treat the pool with a copper algicide. Black algae hate copper and it is a very effective treatment for killing them.
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