Rick, You have the dreaded "string alage". The easiest way to pick it off the
rocks is with a toilet brush. I had my hubby attach a toilet brush to a
handle. Lay the brush flat on the "stuff" and twirl the brush and it will come
right up. There is a something called String Alage Buster but I have never
used it, and others on this board have also used kitty litter. Good luck!!
Jan
"Our Pond" Page
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