Many years ago, when the shark pool was added, there was a, I believe, $35.00 fee, but I guess no one was using the facility so they opted for free of charge. Have done this a few years ago. Yes its fun, yes its scary, yes its very cold and you must be able to swim even though the bouyancy vest they give you keeps you on the surface. There was a submarine along side of the pool with port holes for non participants to see the fish and sharksand people. We did it twice and ahven't been back. For us, once was enough but its a must do!