In today's swimming pool market "mineral" = "copper" or sometimes "copper + silver" or rarely "copper + zinc".
Copper kills algae. Copper kills bacteria . . . v-e-r-y _ s--l--o--w--l--y. Copper does not kill viruses.
In average pools (ie, non-PoolForum or BBB method pools) 50% or more of the chemical use in a typical season goes to cleaning up algae messes. PoolForum pools don't usually have algae messes, and when they do, they usually get cleaned up quickly.
My point? A typical pool with a lot of copper is less likely to have an algae bloom than one with no copper. So, yes if you used a "mineral" system faithfully, your use of chlorine would be reduced, perhaps 50%. So, I wouldn't call it a scam, not quite.
Unfortunately, "mineral" products often turn into a scam when sales people talk about "chemical free" or non-chlorine. Copper is not a sanitizer, because it does not kill viruses and is too slow with bacteria. When people claim you can run a safe chlorine-free pool with "minerals", they ARE scamming you. The companies themselves have stopped doing this, though only after several got hauled into court! But apparently, a lot of sales reps still make those claims, because I keep hearing them from people here.
BUT, if you are a BBB method user, you've already reduced your chlorine use MORE than 50% . . . and without staining your pool blue-green or your hair green. (Copper, not chlorine, causes green hair.)
So, there's no savings for a BBB method user, just more expense and more stains.
Ben / PoolDoc
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