We are hoping to add borates to help the water feel softer and better for the kiddos and us. And to keep the pH steady instead of bouncing all over.What are you hoping to accomplish with borates? Steadier pH? You'll get that if you ever get the TA down to about half where it is now. Every time you replenish the water you're just going to drive TA, and by extension, pH, upwards. And it will take more acid to lower pH once the borates are there. Borates might slow it down some, but again, so will aggressively driving down the TA now.
When you add water, don't just drop the hose in. Rig it with a spray nozzle on a ladder or on the fence somehow so it blasts the surface. That'll push the pH back up fast so you can re-treat it with acid. Devise a jet on the return so it breaks the surface. Acid, aerate, repeat until TA comes down. Then things should stay steadier to where you only need to add acid after water replacement.
That's a great idea on the hose. We don't have to add water a lot but it definitely drives the TA when we do.