I read the manufacturer’s manual on line and also the patent which is also available on line. Their proposed mechanism of the formation of NaCl deposits at the tank’s bottom doesn’t make sense.
Strange as it may sound, what seems like a more plausible mechanism serves their cause even better.
I wonder if any one (chem geek?) is interested in exchanging a few words about it.
If there’s an interest I’ll post a more detailed discussion with links.