Jim from Wisc writes
Can be sprayed on concrete to stop algae
Crystal Blue Copper Sulfate should only be used to control algae in listed bodies of water and for other uses approved on the product label. If it's sprayed on concrete it will stain it. Bayer Advanced 2 in 1 Moss and Algae Killer RTS is another option.
Answer last updated on: 05/19/2021