We booked a tour as I had done this previously many years ago and wanted to share this with my fiance during our recent holiday in Australia.
Green Island is absolutely stunning for snorkelling, we thoroughly enjoyed swimming with the fish and taking in the breathtaking views across the Great Barrier Reef.
The boat taking us over to Green Island and back was very very good, luckily the day was quite calm so it was not a rough ride.
They had forecast a large swirl in the morning which never happened, but sadly they cancelled the Glass Bottom Boat which was part of this day out. It was a real shame because the swirl had passed and the boat was there in the afternoon taking other tourists out.
As an alternative they offered us access to Marineland, which resides on the island. It was no replacement at all! Very small, we did not feel the enclosures were big enough for the crocodiles, and we personally felt it was not very informative at all and very dirty.
We completely understand that you cannot control the weather, but please please do not offer something as an alternative when it is nowhere near an alternative!
Other than that Green Island is as beautiful as it ever was and would highly recommend for people who love diving and snorkelling to go there!