Let's talk about Alkalinity, Calcium and Magnesium in an SPS Tank

[capn_hylinur]

Originally posted by Sara B
Dosing daily I have raised my Mg from the low 1100's to 1250. I still have low Alk at 6.1dKH and CA is at 470. My other system has Mg at 1155, Alk at 7.7dKH and CA at 400. I like to dose slow rather than add the large amounts suggested by the calculators. I'll continue to work on it and try the two part when I'm out of Tech M. I'm also going to get some new test kits as well since these are a bit over a year old (Saliferts).

For my other additives, I use Turbo Calcium for increasing the CA in my new saltwater. I dose Ca in the tank with 400 Ca and I don't dose the other tank as it holds typically at 450 with no additives. I also have the Warner Marine 2 part and use that for daily Alk and Ca dosing.

magnesium is not measured in any of the alkalinity tests nor is calcium so dosing with either isn't going to give you a higher pH

magnesium simply helps you maintain higher concentrations of calcium. I can't remember reading anywhere that corals or fish are affected by high or low or fluctuations in magnesium.

how is your pH---if low you could use kent reef boost--it will raise the alkalinity and the pH (I think it is due to the boron in it)
fluctuations in pH and alkalinity could affect the health of inverts.