Pica Pica should be gone by then
Cave tubing was fun, but not for everyone, moves kindof slow, not sure if the water was just low but there were lots of "butt's up" spots, and it was chilly when you are in the caves, most of the kids were complaining. The zoo was very cool, glad we ended up going, we weren't going to at first. It isn't really a zoo, they arerescued and injured animals, all native to Belize, that they try to put back in the wild, some I had never heard of. My personal favorite was the Harpy Eagle, the black panther was awesome too.
I agree Hol Chan/Shark Ray Alley is a must, don't know of anywhere else you can have such an experience. Enjoy!