I have a Lavac head. Simple. Power boater's don't appreciate them as they are not usually installed in power boats. Amongst sail boaters the are well known.
Lavac heads are great. I have one on my current boat and have had another two on different other boats. Yes they are studs.
Try here for parts:
https://www.sbimailservice.com/mobile/lavac.htm
Should not your regular daily diet provide all the minerals you need -- not counting water? Vegetables, fruit, and protein -- meat, fish, eggs, etc. not enough for mineral intake?
Here is the MSDS:
https://www.happycampersworld.com/wp-content/uploads/2017/11/MSDS.pdf
You will find it lacking as 99% is Monohydrate with an instruction to call them.
One can get the same in Las Vegas, Miami, and a host of other cities around the world... with the benefit of not being confined in a floating Petri dish. Not to be harsh, but those cruise ships would make fine fishing reefs.
I am a firm believer in having a at least one manual bilge pump that can be operated from within the boat (with all hatches closed, meaning not located in the cockpit or having to reach outside in any way.) This is, of course in addition to those DC operated pumps.
This is what I have...
More grist for the mill:
https://www.atlanticarea.uscg.mil/Our-Organization/District-8/District-Units/Sector-Houston-Galveston/Units/VTS-Port-Arthur/AIS/