Ca/Alk/Mag Mess . . . How to fix?

[Enigma]

My calcium really is that low

Just did the tests on the display.

ELOS: 310
Seachem: 300
Hanna Checker: 365 (I may have messed that one up . . . Don't see how it could be that out)

At least nothing is dying, and I know that I really do have a problem.

Will test the new salt water when I get back from buying a better calcium additive to bring it up a bit.