Sorry for the late response.What sort of stability issues?
As to the Sea Lab, asking whether it works is nearly the same as asking if 1/4 teaspoon of baking soda added every day is a good way to maintain alkalinity.
Problems with stability of alk and magnesium
If your tank has tons of corals, I would say it is good. But it is tricky to get the correct dose for your tank, takes a lot of patience and testing, and eventually still need to retest for changes in consumption.is ATI Essentials Pro any good? sorry for getting off topic, was just curious about it