My KH is actually really high, 160ppm, and my pH is 8.2 and I do not use a buffer. I use PurpleUp for my coraline, xenia, zoos and mushroom. Could that cause massive swings in calcium levels? I didnt worry about it before because my Calcium was at 460 about a week ago. I havent dosed in three days, I did a water change yesterday, and today those are my numbers, with Ca at 580.