I have recently changed salt from IO to Fritz RPM because I plan to start adding corals to the DT soon. I still have some IO salt that I didn’t use. The calcium and magnesium are a whole lot lower in the IO than the fritz. Would it hurt the fish in the hospital tank if I changed back to the IO? I measured the magnesium in the IO and it is around 900, calcium is around 320, alk is much higher around 11 dkh or so. Fritz mag is well over 1400 and calcium just over 400, alk is around 8 dkh. Currently they are in the fritz salt but I thought maybe I could use up what’s left of the IO during their water changes.