I think you could rent snorkeling equipment there, but we took our own. Unfortunately ALL 4 of the snorkeling areas were closed, we were not even allowed to walk on the rocks in the tide pools on April 19, 2004. You could only snorkel in the 2 foot deep man-made lagoon, but there was only sand and some shells to look at. Hope you have a different experience.
On a previous trip, I took off my water shoes on land and just wore the fins into the water.