Calcium leaching through the plaster

[GRIESSER072]

I have been having issues with calcium leaching through our plaster for two years now. This year our pool looks much worse. The pool was built in 2009 and the plaster was redone in 2019. I brush the pool every other day. I am not sure if this matters or not, but we have a 28,000 gallon pool. The pool company who opens the pool suggested a full drain and acid wash this year upon opening. We opened our pool on 4/1/2022. Last year we had 2 or 3 calcium spots and after the acid wash we have about 30 of them. It seems like the calcium is "running" in places.

FC: 3-4 PPM
TCL: 3-4 PPM
PH: 7.2
ALK: 78
CH: 262
CYA: 80

I usually have to add a 1/2 gallon of muriatic acid every week.

Don't mind the date on the pictures, I was using an old underwater camera. Any help is appreciated.

 

[jeffchap]

I get these too. I have some smooth river rocks for landscaping and I'll take a relatively flat one of these and rub it on the nodules and they come right off. It doesn't seem to affect the plaster at all.

It's a slow process, but I'm rather OCD and well beyond my acne days, so it gives me something to do.

 

[GRIESSER072]

Thank you!

 

[ajw22]

You have calcium nodules developing. That is caused by delamination between the old and new plaster in spots. Read...

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

 

[GRIESSER072]

Thanks AJW22. I did pick up a pool pumice stone and was able to hit all of the spots tonight. I'll see how they look in the morning but at first glance it looks 100% better. I may just have to keep an eye on them and keep on them with the pumice stone.