thanks for the fast reply i'm flushing the res at the moment. i was running them at 900 ppm on a blue labs monitor and it was droping like they where searching for the nutes but then this showed up its gg#4 first time running them everything has looked good up to this point. medium is hydroton nutes are protek silica at 4ml a gal calmag at 5ml gal use r.o water then i run the gh 3 part at 5ml a gal each with floralicious plus at 1 ml a gal. use this on all my palnts in veg never had a problem. room temp is 78 c02 is at 900 ppm have 4 big air stones in my res res temp is at 64 h.r is at 60%