Newbie recovering after algae fun!

[CallMeIshmael]

Hello All!
First things first- Thanks for such an incredible forum- I've learned so much already, but no doubt have a ways to go. I wanted to post my results so far & make sure I'm on the right track.

We inherited our pool (concrete 23,000 gallon) when we bought the house 5 years ago. We trusted it to pool co's since then, with a range of problems (a whole other topic!), but most recently a massive algae invasion. Couldn't see 6 inches. Ewww!

Before discovering this site, I did the following:

• Shocked with 6 pounds (3 at a time- 2 days apart) of one of ShockXtraBlue 6-in-1 (incl's Dichlor & copper).
• A bottle of water clarifier (PoolTime-no mention of it's active ingredients).
• Ran the filter 24/7 with the vacuum cleaner going to remove leaves & debris.

These steps did a fair job of getting the green out, but left us with a completely hazy white/blue pool. Then I found you guys!
Since I started reading here 3 days ago:

• I replaced our undersized cartridge filter with a 24" Hayward sand filter. (BIG improvement!)
• 1-3 Daily backwashes (before gauge says it needs it) pulling from pool bottom.
• Refilled with fresh water, sprayed on surface to aerate a bit.
• Got a drop test kit- only 4-in-1, but better than nothing.
• Added 2 gallons of 6% bleach (above & beyond shock kits).
• Kept filter running 24/7 with vacuum.

My test results so far are:
May 31st after 2nd 3-lb shock:
Green clearing, replaced by total haze-out!
Chlor: 3+ Strong yellow
pH: 8.2+ Deep Magenta Red
Acid Dem: Oops- no test.
TA: Oops again.

Jun 2nd after 1st gallon of 6% bleach.
Hazy below 18" from surface.
Chlorine: 3+ yellow to orange.
pH: 8.0
Acid Dem: 4 drops (2 1/4 quarts Muriatic)
TA: Still learning...

Today: After 2nd gallon of bleach.
Water is clearing of haze- to about 3 ft depth.
Chlor: 3+ yellow to orange
pH: 7.6! What changed?
Acid Demand: 1 1/2 drops
TA: 180

I think I'm being cautious with the bleach, and I know I need more detailed FC, CC & CYA numbers. (trying to get that tested today at shop). The pool guy came last week and did nothing- Their pink slip is in the mail- LOL!
I think I'm at least getting on the right track, and have my bleach, baking soda, etc at the ready for needed adjustments. Next is a better chem kit & some distilled water for an accurate read of chlorine.
Any tips or details I'm overlooking?
Any reason for the drop in pH?

Thanks for your invaluable advice thus far- I was literally glued to this site for 3 hours when I found it- So much to learn!