non-toxic tile roof cleaner?

The tile roof I asked about yesterday (replacing a tile) also needs cleaning. We'd like to do it ourselves rather than incurring the cost of a professional cleaner and the noise of pressure washing. We also have landscape plants and no gutters, so avoiding damage to plants is highly desirable.
I've found two products that seem to fit these specs: Wet&Forget, and Seal It Green Tile Roof Wash. Anyone have experience with either?
1) Wet&Forget is more widely distributed -- available from Home Depot (online), Amazon, and apparently from Costco (can't find it on their web site but other evidence says they carry it). Reviews on HD and Amazon are mostly very positive. Works slowly but that's fine with us. Would probably require 4 gallons for this house, lowest price I've seen is $33, so about $132.
http://wetandforget.com/index.html
2) Seal It Green seems to be available only direct from the manufacturer. Makes strong non-toxic claims but does say to pressure wash after applying and allowing to dry, which I'd rather not. Cannot find any reviews. Would probably require 10 pounds, for $125 plus perhaps $10 shipping. (It's one of these web sites that won't tell you the shipping cost without entering all your personal details, grrr.)
http://sealitgreen.com/pid-26/tile-roof-wash.html
Edward
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The both tile cleaner which you mentioned I totally do not have any idea about it but I will tell you about one non toxic cleaner its a vinegar if you apply it on tiles and leave it for a some time after that rub the tiles and you will find a clear and clean tile.
--
Neilorrick


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Nobody has any experience with these? ;-(
I got an email response from Seal It Green saying it works fine to "apply our product and let mother nature do the rest", so the pressure washing is not an issue.
Edward
On Wed, 29 May 2013 14:21:22 -0400, Edward Reid

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