A great morning out to see the reef! Ocean Safari take small groups out, so it's well worth a trip up to Cape Tribulation from Cairns or Port Douglas if you're staying down there. I ended up with just 7 others the morning we were there. Our hosts for the trip did a fantastic job of looking after us and were able to explain all the marine life we were coming into contact with and answer any questions which came up. On our trip we had the added bonus of seeing some dolphins on the way out to the reef, and when we were there, managed to catch sight of a dugong which the crew said was an extremely rare sighting. We were also the only boat out at the Mackay reef the day I went, so we had it all to ourselves. As Cape Tribulation is not too far from the reef, this gave us plenty of time to explore. I'd highly recommend giving this trip a try, you won't be disappointed!