I'm really starting to wish I didn't switch over to AquaForest's Probiotic Salt, everything was doing great until I switched. Now, stuff is STNing, having awful polyp extension, dying off etc. I'm not sure what to do, I'm starting to think it's the low nutrient levels of the system. My alkalinity may be the problem, I have slowly been dropping it so It is closer to 7.7 or so. Its around 8.2 Calcium is 420, Phosphate reads 0 and so does nitrate. I have also stopped replacing GFO and have been feeding the corals more often to increase nutrient levels. Please Help before I lose my whole tank over this.