How much Borax do I need to raise my pH?

I believe the amount of Borax I need to add in order to raise my pH depends on:
- the amount of water I have
- the difference between the current pH and the desired pH
- the current Alkalinity

Questions:
1) Does the current pH value matter or just the difference between current and desired?
2) Is there a chart for this somewhere?

I found this elsewhere on a thread (from ChemGeek):

> 17,000 gallon pool - to raise the pH from 7.1 to 7.5 would take
> 39 ounces weight (about 4-1/2 cups) of Borax and the TA
> would rise by 4.5 ppm

How did he know that?

*****

Somewhat off topic background:

My water has been great for 2 years (since I got the pool - have always been using the BBB method).

Recently my water turned cloudy in my above ground pool 17.5k gal).

So I shocked, then shocked again. I added CYA (now up to 75 ; hadn't done that since filling the pool at the start of the season about 40 days ago - was trying to run with less). Then shocked again (and got the FC up to 15 in the process - okay, I got carried away.) I vaccumed (to waste) lots of stuff but am still cloudy.

So I thought I would try to figure out how to raise my pH from 7.2 to 7.4. In hopes of making my water more uncomfortable for "cloudyness". I couldn't find any advice on how much Borax to add. I thought I added about 1/2 a box (2 lbs.) last year to bring my pH from 7.0 to 7.2. My current Alk was 120 and pH was 7.2, so I guessed and tossed in a whole box (4 lbs.) of Borax. (I know now I should have put in a little at a time and kept testing but I was impatient with the cloudyness...) My pH is now at 7.8 or so.

*** So for 17.5k gal. with Alk 120 and pH 7.2 - adding 4 lbs. Borax raises the pH by 0.6 to 7.8. Does that sound right? (It seems to jive with the numbers from ChemGeek (above), but I'm not sure if that's just luck.)

- DeYoung9