We just returned from our first cruise last weekend. Curacao was our favorite stop. We too went to the Seaquarium, but we opted to do their Animal Encounter snorkling offer. Basically, after a short talk about the rules, we were given buckets of anchovies, and turned loose for as long as we wanted in their protected cove. There were all kinds of reef fish, stingrays, pufferfish, and groupers in there. Of course, they were used to having people around touching them, so they would come right up to you and eat from your hands. You could also feed the sea turtles in an adjoining enclosure, through a fence designed to let you keep your fingers. You still have to be careful with them, though, as they were pretty aggressive.
I don't know if it was unusual, but we had the cove to ourselves for about two hours, before a group of scuba divers showed up. Even then, it was not busy. We enjoyed the encounter tremendously.
