X is pretty much right. It takes a tank loaded with stoney corals (like mine) to require dosing along with water exchanges. I don't exchange as much water as X does although our systems are similar in size. So I dose calcium, alk
and some kalkwasser dosed with white vinegar (that's another topic). I rarely ever need to add mag. Only dose if tests show the need, otherwise water exchanges work fine.
Calcium reactors are deluxe and seem to provide a form of calcium the reef likes. But it is a pain. Extra sensors, valves, keeping the reactor full and balanced and toting a C02 tank around for filling. Too much work for me.
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