I've kept crushed coral in the bottom of my RO resevoir for a long time now, with the thought that the neutral(ish) pH of the purified water would dissolve a small amount of the crushed coral, due to the solubility of CaCO3 at low pH.
I have no idea how much *actually* dissolves, I imagine its a very small amount because I've never had to replenish the crushed coral. But, it does make sense, at least in theory, that some calcium and alkalinity is being added via this top-off water. So, to take this theory to its extreme: If enough evaporation was occurring, could the ca/alk needs of the tank be met through the makeup water? I realize this may not be realistically possible, but its fun thinking about.
On another note--how about keeping a high concentration of ca/alk (via B-Ionic or equivalent) in the makeup water? I realize that if its too high, the ca/alk will simply precipitate out of solution. But how about, say, 1000 ppm Ca and 25 dkH? too much?
I have no idea how much *actually* dissolves, I imagine its a very small amount because I've never had to replenish the crushed coral. But, it does make sense, at least in theory, that some calcium and alkalinity is being added via this top-off water. So, to take this theory to its extreme: If enough evaporation was occurring, could the ca/alk needs of the tank be met through the makeup water? I realize this may not be realistically possible, but its fun thinking about.
On another note--how about keeping a high concentration of ca/alk (via B-Ionic or equivalent) in the makeup water? I realize that if its too high, the ca/alk will simply precipitate out of solution. But how about, say, 1000 ppm Ca and 25 dkH? too much?
