Calcium off the charts

[Dunedin1]

I had my pool re-plastered at year. I was only concerned about ph last year.
This year, I noticed long white calcium deposits.
Finally got around to checking everything, all good except calcium is off the charts!

Any options?
The calcium comes from the tap water (dishwater has calcium scale).
My town had well but RPO water supposedly.
Thanks-Alan

Temp 86
ph-7.6
chlorine- 5
cya 70
total alk 70
calcium approx 900+
Salt water pool

 

[Bperry]

I had my pool re-plastered at year. I was only concerned about ph last year.
This year, I noticed long white calcium deposits.
Finally got around to checking everything, all good except calcium is off the charts!

Any options?
The calcium comes from the tap water (dishwater has calcium scale).
My town had well but RPO water supposedly.
Thanks-Alan

Temp 86
ph-7.6
chlorine- 5
cya 70
total alk 70
calcium approx 900+
Salt water pool

Your signature doesn’t say how you test the water. What have the results been over the course of the season? Only way to get rid of calcium is to drain water and replace it with lower calcium water.

 

[Dunedin1]

TFTestkits.

 

[Bperry]

TFTestkits.

I’d think with all the rain you get down there the calcium wouldn’t be such a concern.

If you haven’t been managing your water chemistry to keep the CSI close to zero, it’s possible you could have dissolved calcium out of the plaster. But without test records it’s difficult to know for sure. But your statement about only being concerned with pH may have contributed.

 

[reggiehammond]

Test your fill water for CH and report back. I'm with @Bperry in thinking the calcium may have come from the plaster.

 

[Dunedin1]

ok guys, surprised myself. The RO town water is 100 calcium.
I did read someplace that high levels could be from plaster.
...and in central gulf coast Florida we are down about 8" or more from average summer rain. Dry summer.
I assumed it was coming from adding water. nope.
I test 3x weekly for chlorine/ph, add at least 20oz of acid a week to keep ph in check.
Not sure if I can do much, chip off deposits?

 

[JamesW]

The deposits are nodules due to cracks.

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

 

[Bperry]

ok guys, surprised myself. The RO town water is 100 calcium.
I did read someplace that high levels could be from plaster.
...and in central gulf coast Florida we are down about 8" or more from average summer rain. Dry summer.
I assumed it was coming from adding water. nope.
I test 3x weekly for chlorine/ph, add at least 20oz of acid a week to keep ph in check.
Not sure if I can do much, chip off deposits?

Hard to see what’s what. Looks like there’s at least one crack? You can chip off any deposits, but if you can manage your CSI to stay slightly negative (along with replacing the calcium saturated water) it shouldn’t happen.

 

[JamesW]

calcium approx 900+

This might not be accurate.

Copper and other metals can interfere with the calcium test.

 

[mknauss]

calcium approx 900+

Cut your pool water sample 1:1 with distilled water. Then redo the CH test and double the results.