Question about CH & Lower Freeze Temp

[Eddie&Lynn]

We have an indoor lap pool that we would like to keep open this winter. Last winter we managed to do that by having the pump run 24 hours/day during our coldest winter months. Our lowest temps are in the mid-20s.

I'm wondering if it is possible to lower the freezing temp of our pool water by pushing the CH of our pool to the high end of normal (say 300-350).

Would anyone be able to point me to something that would allow me to determine if that's enough CH to change the freezing temperature of our pool water?

 

[mknauss]

Calcium chloride - water, phase diagram

 

[JamesW]

Adding calcium chloride or sodium chloride depresses the freezing point, but only for significant amounts.

The amounts in a pool are a fraction of a percent and don't make enough difference to matter.