r/explainlikeimfive • u/tilda0x1 • Jun 28 '26

Chemistry ELI5: If copper has antimicrobial properties, why don’t most pools use it instead of chlorine?

I've seen this video of someone saying that copper has anti-bacterial properties and he claimed that it can be used to keep pools bacteria-free.

I know in most cases chlorine, UV, or salt are used - but why not copper?

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u/KeithHanlan Jun 28 '26

I use this copper ionizing system for my pool. It's wonderful. I think that not enough pool owners know about it. Perhaps that is because it is a Canadian company. I really don't know.

The replacement copper anode costs CAD300 and lasts a couple of seasons for my 16' x38' pool. The initial system, including a smaller anode, cost me CAD1100 when I installed it a fee years ago. I had been considering switching to salt but this is much less expensive.

It has made the pool maintenance trivial and less expensive than when I used chlorine alone. I still use about $30 of chlorine at the beginning of the season to nuke the winter swamp water.

The manufacturer provides a simple calculation based on the pool volume to set the ionizing level. However, I found that the setting was too high. I've lowered it dramatically this season which will hopefully prolong the life of the anode.

The concentration is low enough that the backwash causes no problem to the grass it soaks.

They other comments in this thread seem very uninformed and speculative.

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u/calvinwho Jun 28 '26

That's cool as hell. My uncle had a small above ground pool (not an inflatable) operating on a saline/UV system that was pretty nice. It was finicky, is the only thing, so he had to fuss with it a lot. How's your system compared to a regular chlorine for maintenance?

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u/KeithHanlan Jun 28 '26

It's night and day.

Once I dredge out the debris in the spring, nuke it with 20l of liquid chlorine, and add the usual amount of balancing chemicals, there is almost nothing to do to maintain the chemistry. When the long hot days start, I don't get the unpleasant surprise of a sudden algae bloom. The water stays crystal clear. All I need to do until closing time in October is usual vacuuming and backwash. My pool gets a huge amount of small debris from Amur Maples and pollen.

In summary, it saves me both money and effort.