Even as I write this, I feel as if the screen is swaying in front of me. We spent three days living aboard the Reef Experience, out on the Great Berrier Reef. We did ten dives in 45 hours, spending hours submerged at least ten metres below the surface, exploring the reef. It was a phenomenal experience – like swimming in a large tropical fish tank. What a difference to the do-it-yourself dives on camping trips on the cold water of the south coast. This was luxury diving. Our BCs already assembled, all we had to do was shrug on our short wetsuits, weights and BCs, stride into the water, and we were good to go. It was the easiest diving I have ever done, and also some of the most beautiful. After 40 minutes of diving in 29 degree water, we simply dumped all our equipment on the deck, retired to the hot tub, and waited for our next meal to be served. At one stage we were even joined buy a pod of dolphins, leaping through the water as we looked down from the deck. First class service.

We swam with dozens of fish species, sea cucumbers, glowing coral, parrotfish pecking at the coral, giant clams, a feeding sea turtle, a lion fish, barracuda and black- and white-tipped reef sharks. I was cleaned by bluestreak cleaner wrasse, and when I wiggled my index finger at a curious large silver fish as we were descending, it tried to nibble it off.

We were also able to take two guided night dives. On our first we saw sleeping parrotfish, biomuminescence, and a sleeping turtle. The reef was completely different – very few small fish out, and on the second night dive, I found out why. We were jointed by a pack of giant travelli – large black fish stalking the smaller ones like a pack of wolves. They used our torches to spot their victims, and then moved in for the kill. I must have been responsible for dozens of tiny fish deaths that night. It was very sinister yet extraordinary – to be surrounded by complete blackness all but my tiny beam of light, under metres of ocean in the middle of the sea.