uw_gnome
Registered
Hello. My recommendation if you were choosing between the two would be Heron Island. In May there should still be plenty of warm weather. If you want good advice Diversion Dive Travel are based here in Australia and book both the Cairns region and Heron Island. I haven't personally dived Heron Island, but it is on my wish list to do. Green Island I have dived and I do not believe it is what you are looking for.