There is water constantly flowing from the balcony of my neighbor on the asphalt and in turn splashing on the wall.

There's a huge permanent stain there and looks like something fishy:

a wall with what appears to be mottled grey and green discoloration, and pock-marks, near its bottom

Is this fungus?

  • The discoloration, I'm guessing is the cement being tainted by the water. But I'm personally concerned by the greenish spots on the wall. Jun 13, 2017 at 0:09

1 Answer 1


Looks more like algae - wet location, sunshine, photosynthesis, chlorophyll.

  • So does that mean I can leave it in place? Jun 13, 2017 at 4:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.