Moss or algae? How to eliminate?
There is greeny/yellow film on large parts of my shady brick patio, which I can't eliminate - it always comes back. It also appears in moderate sun. I have true mosses growing in crevices in the sunny patio.
The film bothers me more - scrubbing, baking soda, lime,
Clorox, Comet, 409- the film is removed temporarily but returns gradually. Accumulated winter leaves increase the problem - but it is in other areas without leaves - and is very slippery when wet..
I would really appreciate your experience and advice.