Managing CSI with TA, CH

[altapoolguy]

Hello braintrust,

I'm close to opening the pool for the season and my chemistry is nearly perfect except my CSI is lower than I'd like and maybe I need a reality check from someone more experienced.

FC - 4.5
pH - 7.7
TA - 60
CH - 275
CYA - 60
Salt - 3000
Borates - 48
Temp - 71°
CSI - (-.57)

My fill water is very hard and will likely push my CH up by 50 to 75 over the course of the swim season. I lowered my TA down to 70 from about 90. I think with rain water this year it got pushed down even lower.

CSI has been lower than the recommended -.6 for quite a bit of the winter. Even with warmer temps, I'm going to be closer to -.4. I'm worried about damaging my pool or my equipment.

My calculations told me that getting my TA up to about 70 will get me closer to where I need to be. I added 1lb of sodium bicarb today which should bring me up up 64ish and will retest soon but it got me thinking: maybe my CSI isn't that bad? Should I leave it alone and let it drift up a bit over the season? I think even with the additional Calcium from my fill water I'll be just under -.3 with the warmer temps.

Thoughts?

 

[Rancho Cost-a-Lotta]

I wouldn't sweat the CSI for now. Just allow your pH to ride up a bit. Warmer temperatures and top offs due to evaporation will quickly bring you into range.

 

[altapoolguy]

I wouldn't sweat the CSI for now. Just allow your pH to ride up a bit. Warmer temperatures and top offs due to evaporation will quickly bring you into range.

Ok. How bad is it that with low temps my CSI was between -.8 and -.5 for a few months?

 

[Rancho Cost-a-Lotta]

I doubt you'll notice anything. Tfp says CSI between plus 0.6 and - 0.6 is okay. You seem to have a very good understanding on how to get to where you need to be. Do your best to maintain CSI between -0.3 and 0.0.