Every spring we chase ducks out of our gunite pool every morning. We also often have frogs. We are now fighting small black algae spots around the pool which we are told is from things like ducks and frogs. We have tried the black algae treatment recommended by the pool store but it hasn’t helped much. I’ve heard we may need to drain the pool and bleach the pool. Any other suggestions?


Treating these small black algae spots can be difficult. There is one thing you have not mentioned that can really help and that is disturbing the black algae spots. Brush the spots with a stiff brush to break down its outer coating and make it more vulnerable to the chlorine and black algae treatments. Also, if you can direct the water circulation toward the affected area, this can help the chemicals to penetrate. If this does not work and before draining, make sure to spot test on higher up algae to make sure that you can treat the algae as prescribed and that it is not some stain other than black algae.

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