This was the print out from the pool shop.
Fibreglass pool Alk low 67
Ph slightly high 8
He’s stating 4kgs buffer and 600ml hcl acid to counter the ph increase from trying to increase Alk .
I worked out 3.5-3.6kg buffer was needed and added 600ml acid .
I’ll report back tomorrow see if everything settles in the correct ranges .
If it does we could use this to work out the math on it within your app to compensate the ph raising to much with the Alk increase needed.