I find it very hard to quiet my mind.

But when I get in the water, the fact that I'm holding my breath, and I'm going down, I just have to be very in control. Somehow this makes everything seem calm. I have to be calm, to stay in control.

Free diving is just so quiet. Everything is so slow, once you get in the water. You just sit down, watch stuff happening around you. There's no noise, it's silent. It's just this feeling that you're finally away from the buzz, away from everything else.

Video by Aristo Risi (@aristorisi on Instagram)

And you need to be in control, because there are so many things you have to be thinking about. Which to me is just a great feeling. 

You can feel your heartbeat, everything is quiet - you can really feel yourself existing in that environment. That's pretty cool.

The water has a very calming nature - even if it's rough and you're under the waves, just being in water de-stresses you straight away. As soon as you get underwater and start free diving, it's quiet, it's all slowing down.

And everything is so beautiful - the scenery, wherever you go. And it's so beautiful around Wollongong.

If I had to name my favourite spots, I really like trenches. It sounds funny, but I love them. I just like getting in little holes. I like the idea of getting into something that can be seen as a bit, not necessarily dangerous … but yeah, maybe dangerous, in a way.

There are some spots off Wollongong where it's just like a playground - where you wouldn't even know there are trenches, until you push the help aside. I see OK I can fit, I can escape, so I'm never taking a bad risk, and I'm always with my diving buddy.

There's something pretty funny about getting into a little cave, into little trenches. For me Wollongong is really awesome, because there are caves that are pretty safe, not that deep, off South Beach.

There are some deeper trenches off just in front of the lighthouse, but it's very rare that we can get there - it's usually very exposed. It's probably only 20m out, it drops down to about 8-10m. So as soon as it's flat, I say "OK guys, trenches!" and a group of us goes out.

There's nothing that can really scare you. Last time I saw a black fin - I got a little scared, and went to check out what it was.

It was just a seal, around North Wollongong, the headland. She was just chilling, putting her fins out, like they would do when they're chilling out.

I'm not scared about sharks. I honestly think the probability of seeing a shark is very low to begin with. It's not like it's portrayed in the news. I've dived with seals in Narooma, I dive at Port Kembla, and you never see a shark - maybe you might see some smaller ones. But I'm free diving, not spear fishing - I'm not shooting a fish and having blood everywhere, so I'm not attracting the shark.

Reunion Island, where I grew up, is very famous for shark attacks there. We just had a fatal shark attack again - it was last week. There have always been shark attacks but in recent years we've had way more - so that all water activities were forbidden.

But surfers still go surfing. I go free diving whenever I go back to Reunion Island, never seen a shark. My dad goes free diving twice a week, he has never seen a shark.

As a diver, it's in the back of my mind, because the media condition you to think about it, in a way - all the Jaws movies, the fixation on shark attacks, when probably the mosquito kills more people than sharks. But it's such a powerful creature, and it's quite violent when there is a shark attack.

So when I go diving, I sometimes have that thought in the back of my head - when the visibility's not very good or it gets a bit deep. It will cross my mind - but that's it.

Reunion is a small French island off the coast of Madagascar, about 75km from north to south. It's very mountainous, busy, and is surrounded by water. So I grew up surrounded by water - everywhere you are in Reunion, you can basically see the ocean.

I love nature so we're always outdoors - fishing, kayaking. My partner is a great bodyboarder and surfer, so he will always push me. There's never one minute when it's quiet - kayaks on Jervis Bay, fishing on the South Coast. Saturday, we get up and check the sea. If it's flat it's a free diving day; if the swell is up it's a surfing day.

I have a job that is taking a lot of my time - I work for a recycling company. I look after secure destruction of electronic waste, and I look after some of the collection points across the country for e-waste.

I've never been in a really close call. One rule in free diving is that you always have to plan your dive, so you know exactly what you're getting into. I'm always with my competent diving buddy who can rescue me. I squeezed myself into a wreck in Ahmed (Bali) and part of the wreck had collapsed after the earthquake. I ended up under the wreck, but I could get out. That was OK.

This weekend I got slammed by a wave onto rocks at the breakwater at North Wollongong - we were cleaning up fishing waste. 

I can hold my breath about four minutes - but that's not even close to the competition divers. You'd be surprised - most people easily hold their breath above two minutes, if they're relaxed. People say, what if you stay under too long? But free diving is not like skydiving. Skydiving, you're relying more on your equipment. Free diving, I'm in control, because I'm relying on myself, and my ability to not put myself in a bad situation. It's not a competition - you should not want to hold your breath longer than someone else. Stay within what you can do. And you never dive alone.

As told to Ben Langford