Do You Test for Mag?

[saltyhog]

IO Reef Crystals has pretty high Magnesium as I recall but plain IO does not. I have to boost mine with water changes due to IO Mag being much lower than my tank runs.

I test for Mag every couple of weeks which as about how often I have dose it manually.

 

[Randy Holmes-Farley Verified Community Expert]

Randy,

Don't you also use IO? I have read that it is known for high mag so 1600 could be believable couldn't it? My calcium consistently reads 450. If it were too low I couldn't keep that type of calcium level could I?

I used normal IO for many years. Magnesium is not that high unless its a very rare bad batch.

Low magnesium makes it harder to maintain both calcium and alkalinity, since what it does is just allow for more calcium carbonate formation.