Added salt, CSI now -0.8 but I'm hesitant to add calcium

[JJ_Tex]

New pool was filled 4 weeks ago, and we just added salt yesterday.

I ran the full battery of tests this morning before I turned on the SWCG and my CSI is now a -0.80.

My pool logs are updated and I have a few outliers:
- TA is slightly low at 50, but it is keeping the PH in the 7's so I wasnt planning on adjusting
- CYA is low for a salt water pool at 20, but I just turned on the SWCG this morning so was going to get that up later
- CH is 200

I believe CH is my problem, but we have notoriously hard water. I have to use CLR or vinegar on faucets to remove the scale several times a year, plumbing cartridges get gunked up with the stuff, etc. Even though the numbers say to add calcium it goes against my better judgement. I also asked the pool startup guy about it yesterday when he was adding the salt. He said "Our water is hard enough and will come up with the fill water. Once you add calcium you will regret it and have eventually do a water exchange to fix it".

I know TFP doenst put much stock in startup guys, gut feelings, etc. but should I really add calcium?

 

[duraleigh]

Test the CH of your fill water so we know exactly the number.

I tend to agree with you (and the pool start up guy) but post that number before you do or don't do anything.

 

[JJ_Tex]

Test the CH of your fill water so we know exactly the number.

I tend to agree with you (and the pool start up guy) but post that number before you do or don't do anything.

Thanks! I tested my fill water a few weeks ago before I filled and here were the results:

FC - 0.5
CC - 1.0
PH - 8.2 (drop) 8.1 (probe)
TA - 110
CH - 175
CYA - 0

 

[ajw22]

Let your pH run between 7.8 to 8 and your CSI will be fine.

Why did you put salt in so early? PEBBLETEC says wait 28 days.

https://mmgtx.com/docs/PTI-Start-Up-Maintenance-Procedures-Salt-SWCGS.pdf

Your water is going to get too cold soon for the SWG to generate.

 

[JJ_Tex]

Thanks. Plaster started on 9/25, so yesterday was day 28.

 

[ajw22]

With high pH and TA fill water just run them higher in your pool for the winter to offset the cold water and keep your CSI reasonable.

 

[JJ_Tex]

Awesome, thanks guys! Until this post I was going to run out at lunch to get some calcium.

 

[duraleigh]

+1 what ajw22 said!