I don't have any knowledge of the keel on he bottom but I can tell you I spent the night in there in June. I was anchored behind the mooring field and saw several boats go across the reef. When we got up the next morning there was a large bareboat cat behind us on top of the reef. When they pulled up anchor they brought up a huge coral head. When they saw me taking pictures of it they motored over with the rocks still hanging from the anchor and asked how to get it off. I was really glad it wasn't one of our boats.