make sure you take your skimmer cup off because it will overflow during treatment. Airstone is also important because it will deplete oxygen in the water columnI'm dealing with it right now . It always seems to hit when I get lazy and don't monitor my RODI TDS. Then it's manual removal and water changes.. That said, I might grab some chemiclean and give it try.
I have used chemiclean successfully also. Yes it does make your skimmer go bananas. I was also siphoning it out when cleaning the sand through a filter sock holder I hang in the sump.I have been successful increasing flow in dead spots. I had also been successful using chemiclean (you have to make sure you have an airstone in the tank though) = lots of salt creep.