How to prevent scaling while a pool is closed...

[TreeFiter]

This season, I've seen a few plaster pools that accumulated significant scaling over the winter. So it started me wondering how this can be prevented. Once the pool is winterized, nobody is checking and adjusting the chemistry until spring. So there is typically 5-6 months where the water chemistry is not being controlled. So what can I do to prevent scaling during this time? What can I do to prevent etching of the plaster?

Plaster pools drive me nuts because there is a constant struggle to keep the water in the pool from destroying the pool itself. This can be managed during the pool season, but is there a way to make sure there won't be problems over the winter?

 

[chem geek]

Lower the TA and raise the CH before closing. Cover the pool with a solid cover if possible (though some prefer covers that let water through, but those will let gasses escape).

Or err on the side of a lower saturation index and just lower the TA. 50 ppm Borates would help reduce the rate of pH rise. With the pH being higher and the water being colder, the risk of dissolving plaster is significantly reduced.