Need to replace pool water every 5 yrs????

[CarlD]

Yes, I've heard of it. I've also heard of The Great Pumpkin, but like the gents said, that doesn't make it real.

[chem geek]

If you've been using bleach or chlorinating liquid as your source of chlorine, then if you have been adding around 2 ppm Free Chlorine (FC) per day, this adds about 100 ppm salt per month. So if you've got 6-month swim seasons, then after 5 years the chlorine has added 3000 ppm salt -- about the amount found in most saltwater chlorine generator (SWG) pools.

The above assumes no dilution of the water, so no backwashing of filters, no rain with overflow, no significant splash-out, no partial drain and later refill for winter closing.

Richard