I have "cool deck" around my pool. It's white and hard to clean. What can I Use?

Question

I've tried just about everything available at Home Depot & Lowes. Even powerwashing doesn't work.

Answer 1

cool deck commonly develops black algae.  try using a strong chlorine solution in  a pump sprayer, let soak for a few, then power wash

Answer 2

try a flame gun! It won't even be cool then either or dirty!

Answer 3

use a simple clorox bleach