Agree and have the same comment ..................
Used "Wet & Forget" on a very nastily moss covered steep pitched garage roof .......... as it was so bad, I actually made two applications about a week apart. Further, I did not dilute as fully as the instructions suggested (leaving it somewhat stronger)
Now, a month later moss is completely killed ..... but as thinkxingu mentions I have the dead residue still up there ........ and given the pitch of the roof - that's where it will stay!
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