Questions, answered

You need to be comfortable in the water, not fast. For Open Water you'll show you can swim 200 m without stopping (any stroke, no time limit), or 300 m with mask, fins and snorkel, and stay afloat for 10 minutes without help. If you're unsure, tell me. We can check it in the pool before you commit to anything.

Every course starts with a diving medical questionnaire. If you answer "no" to everything, that's all there is to it. If you answer "yes" to any question (asthma, heart or lung conditions, some medications, recent surgery and so on), you'll need a dive medical from a doctor who can issue one, signing you off as fit to dive before any in-water training. Many conditions don't stop you diving, but it has to be a doctor's call, not mine.

Open Water courses start from age 10 (a junior certification until 15). Technical and rebreather courses need you to be 18, and SDI Solo Diver needs you to be 21. Each course page lists its own minimum age.

All my courses are scheduled around you. There's no fixed timetable you have to fit. You do the theory online at your own pace first, then the pool sessions and four open water dives take a minimum of three days, either back to back or spread out to suit you.

All three are recognised worldwide, and their entry-level courses are equivalent: PADI Open Water and SDI Open Water Scuba Diver certify you to 18 m, and RAID Open Water 20 to 20 m. Any of them will be accepted at dive centres around the world. Choose on who teaches you, not the logo on the card.

I teach PADI and SDI independently, and RAID through Perth Diving Academy. If you plan to go on to technical diving, SDI is a natural fit, because it's the sister agency of TDI, which certifies the technical and Poseidon courses.

Yes. Certifications from any recognised agency count towards the next course's prerequisites. Bring your certification card (or app) and your logbook, and we'll pick up from where you are.

Included: eLearning and course materials, the agency course and certification fees, air fills, and on most courses two boat dives.

Not included: equipment hire, and any additional boat dives. If you miss a dive or need to repeat one, I can usually fit it in as a shore dive at no cost. If another boat dive really is needed, that's added. Nitrox and trimix fills are charged for their oxygen and helium content only.

Send an enquiry or call me and we'll find dates that suit you. A deposit secures your place; it usually covers the course materials, and it's non-refundable. The balance is due before the course starts. Payment is by bank transfer.

It's rescheduled, always at no cost to you. Perth's sea breeze and winter fronts do cancel the occasional day. Diving in conditions that aren't safe for training is never worth it.

For introductory courses: I strongly recommend owning your own mask and snorkel, since fit matters and they're personal. Then fins and an exposure suit. Leave the BCD, regulators, cylinders and weights until you're established and know what you like. Until then, hire them from Perth Diving Academy, where we train. They also have a great range to buy from.

For technical courses: you'll need all of your own personal gear (mask, fins, exposure protection, computer) before the course starts, and most of the hardware too (wing, regulators, cylinders). Talk to me before you buy. It's much cheaper to buy once and buy right.

Yes, and many technical students do. One-to-one tuition is a fixed surcharge on technical and rebreather courses: +$400 for Advanced Nitrox or Decompression Procedures, +$500 for both together, and +$300 for any Poseidon course. For recreational courses, just ask.

Pool sessions are at the Perth Diving Academy facility in Hillarys. Open water dives are around greater Perth, from Rockingham up to Mindarie, and often from PDA's boat Wildcat in the Marmion Marine Park.

The ocean off Perth runs from about 16 °C to 21 °C. It lags the seasons by a couple of months, mostly thanks to the Leeuwin Current: the coolest water is in August and September, and the warmest in March and April. The river is typically 1–2 °C cooler than the ocean in winter, and similar to about 1 °C warmer in summer.

What to wear comes down to personal preference. I dive a 7 mm wetsuit all year round, and a drysuit on longer or technical dives.

From me. Roleystone Diver Training has its own compressor for air, and a gas booster to blend any nitrox or trimix mix your dive needs. Air fills are included in your course. Nitrox and trimix are charged for their oxygen and helium content only.

On paper: Advanced Nitrox and Decompression Procedures each need 25 logged dives, and Decompression Procedures also needs an advanced certification. In practice, the more useful test is whether your basics are automatic: buoyancy, trim, and staying calm when something goes wrong. If you're not sure, we can do a dive together first and you'll know.

Most people do. TDI lets them be combined into six dives instead of eight, you finish with both certifications, and it costs $1,575 instead of $875 + $875. The only reason to split them is time, or if you want some nitrox dives under your belt before you start decompression diving.

I teach in back-mounted twins. It's what I dive and greatly prefer, and it's the configuration I'd recommend if you're starting out. If you're already certified in sidemount, I'm happy for you to do the course in that configuration. I'm not a sidemount instructor, though, so I can't teach you sidemount itself.

Those are SDI's prerequisites, and they're there for good reason. Solo diving means there's nobody to fix a problem but you, so the course is for divers whose skills are already second nature. You'll also carry a fully independent redundant air supply. An octopus doesn't count.

A closed-circuit rebreather recycles your breath. It removes the carbon dioxide, adds back the oxygen you've used, and keeps the best mix for your depth throughout the dive. The result is long no-decompression times, a fraction of the gas, warm breathing, and no bubbles.

The Poseidon Se7en (and the MkVI Discovery before it) is fully electronic and designed to be approachable. It runs its own pre-dive checks and manages its oxygen setpoint for you. It's still a rebreather, though, and the training is what makes it safe.

Most divers start with Air Diluent (no decompression, to 30 m), build up 30 hours over 30 dives and six months on the unit, then upgrade to Air Diluent Decompression (to 40 m) or Helitrox (to 45 m with helium).

If you're already an experienced open-circuit decompression diver, with Advanced Nitrox, Decompression Procedures, 50 logged dives and at least five decompression dives to 30 m or more, TDI lets you start straight at Air Diluent Decompression or Helitrox.

Units can be hired for your course. Talk to me about hire. I strongly recommend owning your own from the start, though: you learn the unit you'll actually dive, and you keep diving it the week after you certify.

There are plenty of good second-hand Poseidons around, and I can also source a new unit if you'd prefer. Talk to me before you buy. I'll give you an honest view of whether a unit, new or used, suits the diving you want to do.

I can supply oxygen sensors and scrubber material, or point you to the right outlets.

Not usually as a short crossover. The Poseidon is different enough from other units that it warrants its own training, so you'd do the Poseidon course itself. Your existing rebreather experience will make it a smoother course.

By diving it. Regular dives matter more on a rebreather than on open circuit, because the pre-dive routine and the drills need to stay automatic. The upgrade courses also need 30 hours over 30 dives and six months on the unit, so diving often moves you forward as well as keeping you safe.

Before any Poseidon course or upgrade, I'll ask for evidence of recent diving in conditions similar to Perth's temperate waters.

A rebreather is as safe as the diver using it. The risks are real and well understood: the gas in the loop can go hypoxic, hyperoxic or high in carbon dioxide without you feeling it. The training exists to make the defences automatic. That means disciplined pre-dive checks, watching your handset, and bailing out to open circuit without hesitation whenever something isn't right. Complacency is the hazard, and that's what I train against.

I teach the Poseidon Se7en and MkVI Discovery only. I've taught the JJ-CCR in the past, but I'm not current as a JJ instructor, so I don't offer it. Being current on one unit and teaching it well is worth more to you than being nominally qualified on several.

As a diver, I'm trained on the Poseidon, the JJ-CCR and the Hollis Explorer. If you're weighing up which unit to buy, I can talk you through the differences from experience.