I had the opportunity recently too go diving with the Aquatech dive housing and use Canon inside. It was an amazing day on the island which was full of amazing experiences including, a whale encounter on our way to the dive wrecks.
The whole team at Canon collective made the full day a breeze and I was able to come away with some nice new images. I wish I could have stayed the full three days.
I highly recommend a visit to Moreton Island which is located only a short distance from Brisbane. And accessible mainly by the Tangalooma boat transfers. There is accommodation available at the resort as well as restaurants, cafes and activities.