I fill mine twice a year, with about 5-6 bags each fill. Maybe there are different sizes, but when I was shopping around, most seemed to have about the same cap

I fill mine twice a year, with about 5-6 bags each fill. Maybe there are different sizes, but when I was shopping around, most seemed to have about the same capacity. So for me, I'd say something that takes me about 30 minutes to do (including the trip to get the salt) twice a year is fairly low maintenance.