I currently have a single speed pump that is in better condition than he pool filter but that will also be replaced within a year with a variable speed pump.
You didn't ask, but if you're replacing 2 out of the 3..........
A honking cartridge filter, VS pump and SWG is the only way I'd run.
A Circupool RJ60 would produce 8125 lifetime FC in 28k gallons, even with install, the first cell would only cost about $0.40 per FC. Replacement cells would get about $0.22 per FC and are a 5 min plug and play swap.
Walmart chlorine, for comparison, is $1.71 per FC for you. The RJ60 produces the same as 2257 jugs of chlorine, which would cost $13,903.13 out the door at Walmart, well over $10k more by staying with liquid chlorine. You'd get easier maintenance, a free VS pump, a free filter, and $6k(?) more in the bank.
It's reported here that Circupool is a bit boastful with their production #s, but evenso. If it actually gets 75% of what they say it does, you'd get the easy peasy SWG, the free filter, free VSP and $3k ish in the bank. Boohoo they lied.
