Travis

Depends on your cleaning method. How about some details?

In my roof cleaning business we add Tri-Sodium Phosphate to our Hypochlorite mix. About a quarter of a cup per gallon or so. You can find a box that's enough to make 50 gallons of solution at Lowes for about $20. Look for a red box in the painter's supply section. Be sure that you get the real Tri-Sodium Phosphate, and not the similar, but different non-phosphate substitute. I use so much of the stuff that I'm going to start buying it in 50lb sacks from a chem supply place. Lowes is a good place to get it if you're just testing though. My experience is only with roofs however. Be careful, if you use too much in your solution it can hurt paint, and mess up screens.

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