What are the white flakes in our pool?

[macscom5]

I am seeing lots of small white flakes in our pool. Some are as large as 3/8" across. They are very thin and brittle. I thought they might be salt so I tasted one and it is not salt. The flakes seem to be forming on the plaster surface then coming loose and sitting on the bottom until vacuumed up. Any idea what these flakes are and if this is a problem?

Pool test results:
FC 4.0
CC 0
PH 7.6
TA 90
CYA 60
CH 300
Salt 3300
Temp 88

 

[Melt In The Sun]

Sounds like calcium scale that's falling off the plaster. Your numbers don't indicate scale formation, si it could be old scale.

 

[JasonLion]

Those are calcium flakes. I strongly suspect that they are coming off of the SWG, not the plaster. You should be able to stop them from accumulating by lowering your TA a little, to around 70, or by lowering your PH a little.

 

[macscom5]

Thanks for the info. I can see a few places where similar flakes are attached to the plaster, but very few. The accumulation of flakes is in the vicinity of water returns, so the SWG problem makes sense. I will adjust and see what happens. Thanks, Scott