A- Ayesha and Jacqui’s classes and Charlotte, wanted to know more about the diving. Most of us are diving using scuba gear and breathing from a tank of compressed air on our back. Depending how deep we dive we can stay underwater for 30-60 minutes. The deeper we dive the more air we breathe, which means we can’t stay down as long. On our first dive today we went down to 28 metres – the water is amazingly clear and when we first ducked under the water we could see the people already working on the sea floor! I have to say the water is not very warm – it’s about 17-18 degrees, so even in a thick wetsuit it gets a little chilly. Some of us are wearing wetsuits and others are wearing drysuits – and you can probably guess from the names what the difference is!

I get very wet in my wetsuit, but people in a drysuit wear thick woolly underwear and socks inside their drysuit, which has very tight seals around their ankles, wrists and neck to keep the water out and to keep them warm and dry inside. Malcolm took this picture of me diving at the Cavalli Islands yesterday.

Now I said that most of us are using tanks of compressed air to breathe from. Skip and Richie are using a different, more complicated system – they are diving using rebreathers. They still have tanks strapped to their back, but they use chemicals that take out all the carbon dioxide they exhale and then they re-use – rebreathe – the same air again. The disadvantage is that it’s more complicated, but the advantage is they can stay down for a very long time as they don’t run out of air (this afternoon they went for a two-hour dive). Also they don’t produce bubbles, which can scare some animals away, so no bubbles means they can sneak up close to take photos.


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