problem polyps

you're screwing with the water chemistry. rapid changes are bad, even if they help the parameters of the tank, and the polyps are responding to it. (And purple up is a poor product to begin with: http://www.nano-reef.com/forums/index.php?showtopic=136063)

Why are you adding chemicals to begin with? (Do you test for these before adding?)

yes, i do test its just routine maintanance i only do it once a week and i only add a little water at a time