I have been monitoring my alk every day (mostly) for the past 2 weeks and have seen some interesting trends to which I cant figure out the cause. Tank is a 180 gallon 6x2x2 mixed reef. Three live rock pillars, sea floor special sand (1-2") Fish are: -Dejardini Tang -Blonde Naso Tang -Yellow Eye Kole Tang -Leopard Wrasse -Checkerboard Wrasse -Flame Angel -Blue Chromis x 2 -B&W Ocellaris Clown x2 -Blue Dot Goby So here are the alk readings. Along with Ca, Mg, PO4, NO3. I manually dosed two cups of calcium chloride to get the calcium finally over 400, then in two weeks it went up to 455, this was after I turned the calcium doser down. Alk dosing has been turned down when alk got to 8.46 and up when it got down to 7. It was steadily climbing this week from 7.3 to 7.8,. but then this morning its down to 7.3 again and I didnt change any dosing or anything. I do 30g water changes with IO salt every other week (5/7, 4/23, 4/9, etc). The WC doesnt affect the parameters that much What couldve caused the drop? I measured with Hanna and Salifert to make sure the number was correct. Are these alk swings large enough to affect my corals? My montis are showing the most stress (retracted polyps, BTN) and some euphlyllia doesnt have the fully extended polyps like usual.