I've been battling cyano since February. I must have done 4 treatments with this stuff since then. The last treatment was just last week. I did 3 doses this time, instead of the recommended 2, and used 20 spoons worth for each dose (180g tank with 33g sump. Probably about 160g net, i figure). Last dose was Saturday. 20% water change, fresh carbon back online and skimmer (for what that POS is worth) back online on Monday. Today!......only 5 days later!!....there I see a new patch about the size of a looney on the sand bed!!!! Sheesh. I realize this stuff is not an end all cure but sheesh!!! 5 lousy days?!!! I am getting sooooo sick and tired of this. Can't wait to move and get an RO/DI system going.....and a better skimmer. Hopefully the move won't make it too much of a new tank, yet again.
Anyway, I'm not impressed with this Chemi Clean crap. It gets rid of it, but not for long, IME.
Cheers

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