Is this black algae?

[It's pooler in AZ]

I hammered out a popoff in my plaster pool and found this algae. This was not visible from pool edge, but under the top layer of the popoff bubble. Green and Yellow algae are things I know how to deal with thanks to this site and great test kit, but black algae. Hold me I'm scared....

 

[Texas Splash]

BA? Hummm. Has a bit more of a green color and slimy/gelatin covering than I would've expected, but it sure looks like it would smear green on a paper towel. But let's get another opinion - @JamesW?

Black Algae

This guide provides a step by step procedure for eliminating black algae in your concrete or gunite pool. Read full post here.

www.troublefreepool.com

 

[JamesW]

Looks like it could be black algae.

 

[It's pooler in AZ]

Well, the algae is not smearing well. It is to hard for that. It loses the black coloration when dry with only the dark green remaining. I will try mining a few more pieces with larger black spots and try with another kind of paper but am not optimistic that I will find a slimy chunk. Any other tests besides the smear test?