You could easily have a bad batch of salt. I would suggest contacting the manufacturer with your results. The DKH
after preparing your SW
should be much much higher (double) with a Ca
as high as that. They may request you send them a small sample but IMO
they should replace your existing salt for free.
This could be part of your issue if regular water changes are being performed. The kalk
drip is what would be helping the alk
numbers but at the same time elevating an already high Ca
depending on the CaCO3
demand in the tank. Getting things balanced would be the best direction at this point. Either fix the existing saltmix by buffering before it's used in the tank or get a new batch of salt.
I would still suggest you get the Mg
tested or buy a test kit yourself to test both the saltwater and the tank water. I still strongly suspect that is a contributor as well. The Mg
should be 1200-1400 ppm
based on your salts Ca