Needs for sps

[walleyebum]

i was going to use just cal and alk do i have to have mag?

[karlinkelly]

i was going to use just cal and alk do i have to have mag?

Yes, magnesium is needed to maintain calc levels. Without it, calc levels will just free fall.

[tmgrash]

Depends, I dose 2dkh and 15ppm cal a day and my monthly water changes are enough to keep my mag at ~1350. So test for it and see how much is being used.

[unbreakable]

usually dont test or dose for magnesium unless something is wacky with cal. like adding calcium but unable to increase the number

[allsps40]

I just dose kalk. My mag is kept up by water changes but my salt has high mag.