My Caldera came with the Spa Frog option. It is a very costly solution, the dealer even recommended against it due to cost.
We use 1TBS MPS after each use, and 1TBS Dichlor once weekly along with a Nature2 stick. We change the Nature2 every 4 months with a water change. The tub also has ozone and a circ pump Never had a problem, and much less expensive than the Spa Frog.
Spa Frog, you need to shock weekly, change the mineral stick every 3-4 months, and the bromine every 2-4 weeks.