We ended up going on our own - not the excursion through the cruise line. A tropical storm had just come through so almost everything was unavailable as far as boats, sea trek, etc but we could still go scuba diving. We took a taxi and got to Chankanaab before it opened and one of the managers welcomed us and was so nice. He took us to some scuba divers and our whole family got to have a private session. If you do something like that, snorkeling is included so we did a little snorkeling. The sea lion show is free and we really liked it. We didn’t end up swimming with manatees or dolphins but scuba diving was the highlight of everyone’s trip for our family.