Justa couple of cautions/comments:
CaCl has two drawbacks -- eats the rims as already mentioned and if you get a leak or break the bead, it kills all plant life.
Regular antifreeze has one drawback -- get a leak or break the bead and you have a fluid that is tasty but poisonous to many animals (dogs and cats for sure).
Windshield washer anitfreeze and RV antifreeze are safe, but fairly expensive options and hard for self installation.
RimGuard is also relatively problem free, but difficult to find in some areas.
My tire guy filled mine with a methanol/water mixture -- safe if it leaks, kills nothing and not as expensive as some of the proprietary products, but it doesn't inhibit rusting rims -- tubes are the best answer for that I think.