What causes Calcium to rise?

[SoCalBoo]

Opps, and meant Ph has been above 7.2, above.

[waterbear]

The only problem I can see is the chance of increase scaling in your SWG as the pH rises. There is an alternative to draining and refilling. Calcium is a metal and there are metal sequesterants that are more sepcific for calium than others. Google 'calcium hardness reducer pool' and you should come across several. Just be aware that they do not remove the calcium. Just make it so it cannot react and form scale. Don't know how effective they really are but the chemistry behind them is sound. You will need to keep up with the maintenance doses just like with any other metal problem, however.
I have also seen a product from LoChlor, which Poolsean said was a sister company to AutoPilot Systems, that puts magnesium in the water so the scale that forms on the cell is soft and mushy and will wash off easier. Might want to check with PoolSean on this one.

[let_her_flicker]

You can always check over in the Chlorine Feeder and Salt Water Generator section for scaling issue with SWGs and high CA. I am not familiar with that, but there are others over there that could address that possible issue.

I remember that this site was established to avoid adding other things to your pool. The more chemicals you add, the more problems you could incur. Don't forget that rain water will enter your pool too (hopefully) and that will not have any calcium in it.

Take Care.

Harry

[waterbear]

but, depending on water conditions, some extra chemicals like sequesterants, could be necessary!

[SoCalBoo]

Thanks guys. Just worried about the SWG and the heater (pentair MiniMax NT). Draining 1/2 of the pool and rebalancing frankly sounds cheaper and easier than replacing the heater and cheaper than replacing the salt cell. Admittedly, I have NO idea about how long it would take the elevated level of calcium to render either unusable. Haven't made up my mind yet, so just reviewing my 'options'.

As for rain water, I live in san diego, so not expecting much help there.

[mas985]

SoCalBoo,

I am in a similar situation and just replaced some of my water when my CH got above 400. I started to see some scaling on my SWCG when my PH got above 7.6 so I did a partial refill ~25% and keeping my PH between 7.2-7.4 has so far eliminated the scaling.