Originally Posted by Beemerboy
I have no experience with this product, but have read many times of the years on this subject that Amazing Roll Off is product that will remove, algae and moss on cars.
I've got mixed feelings about ARO. Yeah, it cleans tires, whitewalls and wells nicely, but no better than other less expensive products, IMO. AFA mold and algae removal, I found it disappointing, especially considering that's touted as one of it's prime uses. Sprayed down some white plastic patio furniture before storing it for the winter and 1:1 didn't touch the gunk. Full strength was equally disappointing. I ended up using Bleche White 1:1 and that took care of it.
Interestingly, Westley's BW and ARO have a similar appearance and smell. Bleche White is a much more caustic formula though. You don't want to get it on uncoated aluminum or you'll be in for a lot of polishing.
As for mold, mildew and moss on other than car surfaces, I used a product called Wet and Forget on the black algae streaks on my shingles. Works as advertised! It also works well on patios, concrete and dechs, Welcome to Wet & Forget