No Borax, that makes the pH go UP, not down. You need muratic acid to lower the pH.
Go to lowes, Home Depot or most other big box stores and pick up a gallon of muratic acid. You wan the full strength acid, they call it 31% or 20 Baume. Skip the green, less fume, environmental friendly acid as it is just 1/2 strength for the same money.
WalMart says your pool is at around 10,000 gallons so right now you need to add 19oz of full strength acid. I estimated just a little low so that you wont go too low. You may need to add some more later in the day.
With kids splashing, the pump running and other forms of aeration (fancy word for splashing/activity in the pool) your pH will continue to rise. Because of your high TA it will probably happen quickly so you may be adding acid each day for a while. The acid reduces both the pH & TA but the aeration only raises the pH. So, in time with multiple acid additions your TA will fall into a reasonable range and the pH rise should slow. The relationship between pH & TA is confusing to many folks, so don't sweat it right now.