Welcome! Sounds like quite a busy pool you have. Actually, toadlets are pretty tiny (size of a small pea) and the tads are completely black. Green tree frog tads are bigger than toad tads and they aren't so dark. Leopard frog tads get to be about the size of a dime (without the tail). I've not seen other tree frog tads (at least that I could identify as such). Tadpoles of one species can eat those of another and some are even cannibalistic, but other than removing them and separating them, I'm sure what you can do to prevent that. It becomes more of a problem as the pool of water shrinks. You might capture and add some rain water or well water (assuming it's not treated with chemicals) to keep the water level up.
If there are treefrog tads in there, the froglets won't have any problem climbing out. Toadlets might and if they are fully metamorphozed it wouldn't hurt to give them a helping hand.