There are two solutions to your problem:
The simplest and least expensive solution would be to replumb both toilets to use pressurized flush water as they were design to do and add 4 tablespoons (2 coffee measure spoons) of solar salt to each flush. I've known a number of people who keep a big Rubbermaid box of salt in the head to do it this way 'cuz they either don't have room or don't want to spend the money to add a salt tank. Or, if that's too much effort...
1. Replumb the toilets to use pressurized fresh water as they're designed to do and add a salt feed tank--either this one 4 gallon salt feed tank owners manual
or this one 4 gal salt feed tank w pump owners manual
, depending on which is the right one for your toilet..I'm 90% certain it's the one WITH PUMP but it's Saturday so I can't call Raritan to ask 'em. You can give 'em a call on Monday to find out: 800-352-5630
Solar salt is recommended because it dissolves much faster than table salt. It's available from most big box hardware stores. Inexpensive and a 10 lb bag lasts several months.
Either way has to be easier than cleaning out the flush water intake system with muriatic acid every couple of weeks.
"If you can't explain it to a six year old, you don't completely understand it yourself."