I am having two issues, which I suspect are related. The first is that my CH keeps trending upward. The second issue is that I have just noticed white spots forming on the plaster. Normally I’d say the answer is obvious and the spots are calcium nodules, but I don’t think it’s as straightforward as that.
First, the CH levels. One year ago, my CH was holding between 850-900. This year, I’m up around 1050. We use softened water to top off the pool, and I confirmed that the fill water is CH 0. The last time that we did even a partial drain & refill was July 2022, when the pool was replastered. Following the start up procedure at that time, our CH was about 500, and it has been steadily increasing since. I can certainly do a partial drain & refill, but I am befuddled as to how the CH is increasing when the refill water is soft? We are on a well, and I suppose it is possible that metals in the well water are somehow factoring into the picture? The pool is covered and screened, so evaporation is somewhat less than a “typical” pool in the sun, and very little “stuff” tends to fall into the water. The one exception is that the flagstone coping has been flaking, and small amounts of flagstone dust do get into the pool. I’m not sure if the stone could be contributing to our CH? The water is crystal clear, and I generally maintain a good CSI.
Secondly, I just noticed about a dozen small white spots on the plaster. They are on the floor and on the steps. Unlike calcium nodules, though, these spots seem to be totally flat or possibly even slightly depressed. They also developed very suddenly. Nothing has changed with the pool management. The only change is that this year we switched from a DIY solar heater to a Heliocol solar heater, but I can’t imagine that has anything to do with it. Other than very occasional CYA additions, all that we add to the pool are 10% bleach & muriatic acid. Beyond that, we just try and do a good job with vacuuming, cleaning the filter, and brushing every week or two.
I’d really appreciate any help with figuring out what’s going on. I’m finding the whole thing- especially these new white spots— to be pretty alarming.
Here’re some additional details that might be helpful:
Pool Math records: PoolMath Logs
Plaster: Finest Finish Laguna Microfusion
Replaster date: July 20, 2022
Start-Up Procedure: 28 day cure, NPT start up procedure
Test Kit: Taylor 2006
First, the CH levels. One year ago, my CH was holding between 850-900. This year, I’m up around 1050. We use softened water to top off the pool, and I confirmed that the fill water is CH 0. The last time that we did even a partial drain & refill was July 2022, when the pool was replastered. Following the start up procedure at that time, our CH was about 500, and it has been steadily increasing since. I can certainly do a partial drain & refill, but I am befuddled as to how the CH is increasing when the refill water is soft? We are on a well, and I suppose it is possible that metals in the well water are somehow factoring into the picture? The pool is covered and screened, so evaporation is somewhat less than a “typical” pool in the sun, and very little “stuff” tends to fall into the water. The one exception is that the flagstone coping has been flaking, and small amounts of flagstone dust do get into the pool. I’m not sure if the stone could be contributing to our CH? The water is crystal clear, and I generally maintain a good CSI.
Secondly, I just noticed about a dozen small white spots on the plaster. They are on the floor and on the steps. Unlike calcium nodules, though, these spots seem to be totally flat or possibly even slightly depressed. They also developed very suddenly. Nothing has changed with the pool management. The only change is that this year we switched from a DIY solar heater to a Heliocol solar heater, but I can’t imagine that has anything to do with it. Other than very occasional CYA additions, all that we add to the pool are 10% bleach & muriatic acid. Beyond that, we just try and do a good job with vacuuming, cleaning the filter, and brushing every week or two.
I’d really appreciate any help with figuring out what’s going on. I’m finding the whole thing- especially these new white spots— to be pretty alarming.
Here’re some additional details that might be helpful:
Pool Math records: PoolMath Logs
Plaster: Finest Finish Laguna Microfusion
Replaster date: July 20, 2022
Start-Up Procedure: 28 day cure, NPT start up procedure
Test Kit: Taylor 2006
