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It is my personal understanding, based on research, that SH (Sodium Hyprochlorite) is basically a CONCENTRATED SALT.

That is its BASIC CHEMICAL COMPOSITION.

And Concentrated salt kills plants when directly in contact with most LIVE foliage, hence the bagging of downspouts and the covering of sensitive plants, trees and flowers that may become exposed to it

When diluted substancially it loses it chemially reactive nature, AND over time BREAKS DOWN, mainly into a SALT by product which, again when diluted substancially with H20, poses no serious risks to groundwater from all the research I have gathered so far.

You can PROVE THIS by taking a bottle of store bleach from last year and testing it with a Squibb strip or pool chlorine kit and you will see that the active chlorine has essentially lost its potency, over time, as compared to FRESH SH.

I may be wrong, but this is the basis for why ARMA recommends the use of SH.

Because it cleans the surface we are trying to remove algeae from and poses the least threat to the environment.

As for TSP and Borax, check with your local DEQ and EPA regs, concerning its use for commercial applications to be sure and to avoid problems in your LOCAL area.

-- Edited by Roof Clean USA at 13:25, 2009-02-27