What does black algae look like?

Black Algae looks like small bluish-green to almost black nodules growing on the surface where circulation is low. 

Example of black algae growing on plaster

We recommend using Swamp Treat.

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• What does yellow/mustard algae look like?

  Yellow/Mustard Algae looks like mustard colored growth along the walls and in the shady areas of the pool. It's light, soft and slightly slimy to the touch. Example of mustard algae growing in pool We recommend using Yellow Treat.

• What does green algae look like?

  Green Algae looks like green growth usually along the walls and areas with low circulation. They feel soft and sometimes a bit slimy.  Example of green inground pool Example of green algae growing in above ground pool. We recommend using Green Treat. ...

• What does pink algae/bacteria/slime look like?

  Pink Algae/Bacteria/Slime looks like reddish pink jelly-like slime growing around fixtures and the bottom of the walls.  Example of pink bacteria growing along wall transition. We recommend using Pink Treat.

• What does silver staining look like?

  Silver Staining looks like light grey to almost black stains flush with the surface.  Illustration of gray silver stains in pool To remove it, we recommend Pool Stain Treat. You can find detailed instruction on the Directions tab of the Product Page.

• Can I swim in a pool with black algae?

  For the most part, yes. However black algae (cyanobacteria) can be toxic if ingested in large enough quantities. While swimming, be careful not to ingest any of the black algae growth.