Needing advice reef chemistry

[sobe]

Ill head to j&l to get a salinity calibration fluid to check my refractometer. Ill do a 30g water change in 5 days interval to see if i can get mag up through water changes before i dose.

I just switch from AF salt after using up last of IO bucket.

Will test the new batch of salt mix to see if lines up with their test included on the bucket