Chips in plaster w/calcium deposits

[kokkelez]

Second year with my new pool, which we had built in Fall 2023. It’s about 19k gallon plaster with SWCG.

We’ve kept the CSI in check through all seasons, with it typically running low (around -.20) in winter, but never lower then -.60. The only calcium deposits we’ve noticed are in the SWCG. Today, I noticed two spots and both seem to be just below a chip or crack.

What do we need to do to prevent further chipping? Should I fill these now? Am I running too low CSI?

FC 9.0
CC 0.5
pH 7.6
TA 80
CYA 70
CH 425
Salt 3200
Borates 56
CSI -.21
Temp 77*

Thanks!

 

[PoolStored]

Today, I noticed two spots and both seem to be just below a chip or crack.

Post pictures.

 

[ajw22]

Welcome to TFP.

Calcium below a chip or crack is probably a form of calcium nodule and delamination.

Calcium Nodules in pools

What are calcium nodules? In swimming pools and spas, they are small mounds, bumps, deposits, or “slag” piles of calcium carbonate which are formed from material that has been released from the plaster. The small calcium nodules are rough to the touch, hard, and generally gritty. Nodules may...

www.troublefreepool.com

Do the chips and cracks form over the winter?

Plaster Installation and Maintenance - Further Reading

www.troublefreepool.com

Seeing pictures would help us understand your situation.

 

[kokkelez]

Apologies. I attempted to attach pics but they were too large. New pics below.

 

[ajw22]

Those are calcium nodules.

 

[kokkelez]

I read through the linked nodules post. Thanks for the info and identification. Looks like I have some sanding to do. Any recommendations on epoxy products to use for filling?

 

[ajw22]

I read through the linked nodules post. Thanks for the info and identification. Looks like I have some sanding to do. Any recommendations on epoxy products to use for filling?

I would not bother with epoxy. Just scrape off the scale as it accumulates.

If you must...

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