I don't have a alkalinity analyzer/doser hence make additions manually. The entire volume of this system is about 140 gallons and I mix and add the supplement according to directions. Still, the alkalinity is anything but stable. All corals (including Montiporas) are thriving, except for one chalice that has a patch of zoox loss. I should mention I analyze alk with a Hach digital titrator that reports to a part per million.So the monti is either getting a brownish tint where it was white or it's turning back red. The parts that were pink are much redder also and the polyps seem more red and extended than they did a few days ago. Are monti's really this sensitive to low alk? Fingers crossed that it keeps showing some improvement.