Chances are the kids splashing in the pool is what is causing your pH rise--but the trichlor tabs should be helping to hold that in check. Can you direct your return so that it doesn't ripple the water? Any form of aeration will help the pH rise.

I think you'll be fighting a losing battle to try to lower the TA, because the TA of your fill water is so high--everytime you top off the pool, you're going to be raising it right back up again--I think I would leave it alone.

What makes you want to drop the trichlor and switch to dichlor? You can do either one--they both add chlorine, add CYA (the dichlor adds it quicker than the trichlor), and lower pH. Why don't you go ahead and use up the trichlor that you have, and then make that decision later?

Glad your pool is back in business, and that you are able to enjoy it this season!!

Janet