Auto Fill with Extreemly Hard Well Water or Softened Water and SWG?

[cheddar85]

Yes the CSI goes infinitely negative when either TA or CH become 0 since the logarithm of 0 is negative infinity. That does not imply anything about the rate, however. It just means there is no calcium or no carbonate in the water. The rate of plaster degradation is accelerated by low pH, but a zero CH doesn't instantly cause degradation. And of course if it's a vinyl pool and not plaster than this doesn't matter. It also has little to do with metal corrosion where again the pH is the dominant factor.

A CSI of -0.3 means that either calcium or carbonate or their product is half the amount at saturation, -0.6 means it's one-fourth, -0.9 means one-eighth, etc. So being near saturation slows down dissolving of plaster but there is a limit to its rate of degradation and that rate is more a function of pH than anything else where low pH dissolves the calcium carbonate in plaster faster.

Richard, I completely defer to you on the matter of CSI :bowdown: just an off the cuff remark. If only I had a plaster pool to use all the calcium products I have now!

Patrick, I understood what you meant. I was just pointing out even if the resin bed is iron fouled, it only needs to be cleaned, not replaced. The majority of the time, the resin will actually outlast the rest of the softener anyways. It's really a moot point though, because using a water softener to fill a pool just takes too long. It was just the best way for MY situation, not the majority of pool owners.

 

[Swampwoman]

Patrick, your comment came to mind when I was spewing swamp water coffee the other morning after what's obviously a softener regeneration issue I'm having a replacement dual tank with citric acid cleaning installed next week Hope the AA does its job on the resin fouling ...

Tip to the OP: if you use you softener for auto fill, you may want to estimate how much auto fill uses in a single run and make sure you never exhaust the capacity of your softner.

I got lax last week and topped up a good few inches after a lot of evaporation and didn't check the softner for capacity. My TA shot up and we were drinking swamp water for a spell Lesson learned...go dual tank