IS my PH too high

[gkarag]

I have 65000 litre concrete plaster pool with a SWG unit and I have the following numbers as per my Taylors kit.
CL=1.60 PH=7.7 TA=100 CH=130 CYA=0 Water temp 16 celsius
My Lsi index is -.42 as this is not too bad as water will warm up shortly. Is my PH high and should I be trying to get PH to about 7.5 but if I do, that pushes the LSI to -.62 which might be getting up on high side.
What should I do push the CH up to about 200 so I can get the PH down a bit?
Thaks in advance

 

[JohnT]

Your CH needs to be more like 250ppm with plaster.

 

[RobbieH]

7.7 is acceptable. If it is stable there, I'd leave it alone, but I'm betting with that TA of 100 along with an SWG, your pH is going to float up. If so, you might visit Pool School and How To - Lower TA. And John is right, your CH needs to come up.

 

[Aquatica]

yeah your TA is too high and pH will climb faster. we like to run TA at 70-80 so pH is much more stable and compensate a lower TA with a higher CH like 300-350. you can keep pH higher at like 7.8 to balance better in colder water. we like to aim for a CSI of -0.2 to -0.3 which helps keep cells clean.