the side of the red sea pro salt bucket says that a level of 450ppm of calc will be at 1.022 and the higher the SG the higher the calc level goes. I kept my SG at 1.024 so i have a calc level of 520ppm. This was checked with a api kit and verified with sailfert so i know its right. And it is the same reading with freshly made water before added to the tank. So question one is....will my calc being 520ppm hurt anything? Should i lower my SG to 1.022 to lower calc? Should I just switch salts? I have a half bag of IO left although i think its crap. Everything is doing fine from what i know.