Pool Maintenance Tip #3 in our Pool Algae Series – Black Algae When dealing with algae, the worst of the bunch is Black algae. Black algae tends to form in cracks/crevices in the pool surface, starting as black or blue/green spots about the size of a pencil eraser. It has strong roots and a protective shell which makes it highly resistant to chlorine. The key word for eliminating black algae is persistence. You need to brush the spots firmly, with a wire brush if available, and then apply chemicals directly to the spot if possible (always use caution concerning your pool finish). You then need to monitor the spots daily and repeat until they are gone. Finally, if your pool is covered with black algae the best course of action would be to have a professional drain and acid wash the pool. This will save you time, money and probably your sanity. For more pool maintenance tips, check out our blog or find us on Facebook. For help with any algae problems, call your Houston Pool Builder, The Pool Man, Inc’s service department and schedule your service call.