PH won't go/stay up

I've been working on opening my pool for over a week. Chlorine is staying very low .6-1.2, CC been everywhere from 1.5-3.0. I've shocked and shocked to breakpoint once, that brought the CC down to where it is now. All the while, PH staying at 7.2 no matter how much Borax I add to get it to 7.6 where I like it. Last evening I added 8# Borax. Today's readings from this evening and what I did to address them:

FC 1.0 (added 3# PoolTime 4 in 1 Chlorinating/Shock granuals)
CC 1.5
PH 7.2 (needed 8 drops to get to 7.6 so I added 6# Borax)
TA 100-110
Calcium 170 (it was at 30 when I started and now it's stable at 170)
CYA 48

I'm still running the pump 24/7 until I get it where I want it. Why is my PH not going/staying up?
Why is my FC not staying up? Why is my CC fluctuating so much? and so high?

18x36 inground vinyl, 25K gal, sand filter, polaris, BBB for most part until I tried to do breakpoint shock.

Could you post what the label shows is in the 4 in 1?

I suspect that something in it is driving your pH down.

About your CC: You probably are fighting the beginning of an algae bloom, and will need to add plain household (unscented, etc) bleach to bring your FC level up to ~15, ( Bens best guess chart )and keep it there until you lose <1 FC overnight, and CC remains at 0.

Thanks! Here is the ingredient list of the 4/1 product:
Pool Time Chlorinating Granules PLUS - Sanatizer plus Shock

Trichloro-s-triazinetrione 87-90-1 71.8 %
Boron salt 5 - 10 %
Trade secret 001 5 - 10 %
Trade secret 099 10 - 15 %
Formulated with sunlight-protected chlorine, special clarifier, filter enhancer and algae inhibitor
Helps kill bacteria and algae
Helps destroy swimmer contaminants
Helps clear cloudy water
Convenient skimmer application

Charlie_R is right, the trichlor will drive your pH down. I wouldn't put any trade secret in my pool - it's usually stuff that makes pool care more difficult and expensive in the long run.

I would be willing to bet that at least one of the "trade secret" ingredients on that list is a metal ion, probably copper sulfate pentahydrate. From my reading of various pool chemical concoctions, this is a very commonly used algaecide. The other "trade secret" would be the "filter enhancer", and as BigDave suggests, may not be something you would want in your pool.

From wikipedia: Boric acid has antiseptic, antifungal, and antiviral properties and for this reasons is applied as a water clarifier in swimming pool water treatment. So that would be the clarifying agent, under a less common name. Nothing really "special" about that! [marketers -- gotta love them!]

I am curious, did your test results come from a pool store or from a K-2006. I question this because of the CYA reading.

Test results were mine from a K-2006. I testing this a.m. and the FC was 2.4 and the CC was 2.4, the PH was 7.2, so it's clear that my keeping on adding the 4# of Borax is being defeated by something in the 4 in 1. I am going to try to break the CC down with Chlorox. Just have to figure out how much I need to get FC to 15.