Staining and Cracking in Plaster Pool

[PratikA]

Hello All,

My first post! Recently, we drained our plaster pool after it had been unopened for 3 seasons. We wanted to do an acid wash and start using the pool again. It rained yesterday and I noticed some red spots forming in areas of the floor where the water would not dry. Is this some sort of rust? Will the acid wash get rid of it? Also, the floor of our pool seems to be cracking all over, does this mean we need to redo our plaster? If so, what could I expect the cost to be to replace all the plaster (it was originally dark grey)? I am in Massachusetts. Thanks for the help.

 

[mknauss]

Welcome to the forum!
Completely draining a pool comes with risks. If those spots are not drying, there is a good chance that ground water is coming through cracks in the gunite. The pool can pop out of the ground if emptied and you have a high water table.

I suggest you read ABC's of Pool Water Chemistry.

 

[PratikA]

I do not think that is groundwater as that is only the shallow end of our pool, the deep end has a hydrostatic valve in the main drain that is letting water in slowly every day. There is about 2ft of water there right now. Would groundwater still seep in through the shallow end even with a hydrostatic valve? Also, the spots have dried now after two days.

 

[mknauss]

Great. With that information you are most likely OK.

Probably time for a replaster.

 

[PratikA]

Yes, that's what I feared. The plaster is original to the pool though, almost 15 years old, so not totally unexpected!

 

[mknauss]

Properly maintained water chemistry should let plaster last much longer. But if you were going to acid wash, the water chemistry has not been maintained in the past.

 

[mikes112]

Are these the kind of cracks you have? I know because I did have some ground water come through my plaster too. DId you just replaster or did you have to staple the concrete?