Chlorine is probably the easiest and best way to achieve correct pool sanitation for residential pools, and I don't see any other cheaper and viable options on the horizon.
If there were cheaper options out there that worked, no doubt we would be using them.
I gather you are well informed on being able to run variable speed pumps at low RPMs to save power and the myth about water turnover requirements which seem to perpetuate through various sources....
Are you utilising a SWCG for your chlorine or are you manually adding chlorine to the pool yourself...?
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