Assistant Instructor

Assistant instructors are authorized to teach all aspects of skin and scuba diving under the supervision of an instructor. By working side by side with an instructor, you develop the necessary skills to be an instructor. The assistant instructor program is designed to introduce you diving instruction basics and test your in water ability to be capable assistants. Consult you local dive shop or training agency for course requirements and expectations.

Assistant instructor certifications require specific prerequisites, and these prerequisites differ amongst training agencies, so it’s important that you contact your local dive shop or training agency to find out everything you need to know before signing up for a course.

Wreck – FAQ

Frequently Asked Questions
What’s there to see on a wreck dive?

There is a lot to see on a wreck dive. Intact wrecks sitting upright or on their side are impressive sights under the water. Deck rigging, stairs, stacks, hallways, cranes, propellers, are all examples of what you’ll see on a wreck dive. The more intact the wreck, the more you’ll see as it was when it sailed the seas. Wrecks that have been damaged or destroyed could be simply debris mounds on the bottom or pieces of the wreck could be spread out in a large area. Either way, there is always something to see on a wreck.

In addition to the wreck itself, there are always large amounts of fish and other reef creatures on wrecks. Wrecks are basically artificial reefs that provide shelter and homes for a variety of marine life. Large and small fish, sponges, corals, eels, etc. are all common on wreck dives. The different types and species of marine life you see on a wreck are dependent on where you’re diving. Warm water wreck diving in shallow water will have many “reef” type species. Colder water and deeper wrecks offer many other kinds of marine life than what you’d see on a typical reef. Research the area you plan on diving so that you know what you might see while diving.

Where do I go to dive wrecks?

There are wrecks all over the world that you can dive. The most popular areas for wreck diving are the Atlantic coast of the U.S., the Great Lakes, Truck Lagoon, and Bermuda. Other areas also offer great wreck diving, so no matter where you go on your next diving vacation, there is probably a wreck you can dive.

Do I need a special certification to dive wrecks?

This depends on the kind of wreck diving you would like to do: exterior exploration of the wreck or interior (penetration) of the wreck. Exterior exploration involves exploring the outside of a wreck. There are a number of training agencies that offer basic wreck certifications, which cover mostly the hazards you may encounter. These hazards are disorientation, sharp metal edges or objects, and entanglement hazards created by rigging, nets, and fishing line. To dive wrecks within the recreational diving limits can usually be done with dive operators if you have advanced training or a previous logged wreck dive.

If your interest lies in penetrating a wreck to find out what’s inside, even if it’s in recreational diving limits requires special training. When you enter a wreck, you enter an “overhead” environment, meaning that there is no way to return directly to the surface. Exploring the interior of a shipwreck is both alluring and can be very dangerous. Whether looking for artifacts or trying to find the engine room, penetrating a wreck, no matter what the depth, is an advanced form of diving, similar to cave diving. This type of wreck diving requires special equipment and training because getting lost is a real possibility if you don’t know what you’re doing.

Do I need to purchase special gear to wreck dive?

Depending on the type of wreck diving you’re planning to do, there is some basic equipment you should probably carry while wreck diving. Wreck penetration dives require much more training and have a special list of equipment that is required to safely penetrate a wreck.

Dive knife, line cutter, or scissors: This can be critical. Wrecks are favorite sites for fishing because that’s where the fish are. This means fishing line, leader line, etc. can cover wrecks and can entangle you.

Dive light: This adds immeasurably to your enjoyment of seeing the wreck better. If you’re diving shallow tropical waters, you may not need a light, but diving in less tropical areas where visibility is less, a good dive light is a must. A dive light restores color and helps you spot things easier on the wreck.

Goodie bag: If you plan on hunting lobster, fish, or plan on collecting artifacts in areas that allow this, a goodie bag or catch bag is important.

Get an AED and Don’t Pay

by Colum Sullivan

HeartSine Samaritan AED

The Automatic External Defibrillator (AED) was introduced over two decades ago. It is designed to administer an electrical shock to a victim’s failing heart in an effort to restore a normal heartbeat. Over the years, the AED has become remarkably effective at saving lives, its ease of use has increased substantially, and its purchase price has come down dramatically.

 HeartSine Samaritan AED

How successful is an AED at saving lives?

On land, when an adult victim’s heart stops, it is most frequently due to the naturally occurring deterioration of the health of the heart due to age or illness. Nonetheless, on land, when a victim suffers cardiac arrest, the immediate application of an AED to the victim’s chest has proven successful in restarting the victim’s heart approximately 74% of the time.*

In water, when a victim drowns, an AED has proven to be even more effective than when used on land. The reason for its increased effectiveness is, in part, due to the fact that when a victim drowns the heart stops abruptly and the health of the victim’s heart is usually not an issue. Consequently, in drowning cases, where an AED is immediately applied to the chest of a drowned victim suffering cardiac arrest, the AED has proven to be up to 97% effective in restarting the victim’s heart.*

How do you use an AED?

Unfortunately, too many laypersons are intimidated by the AED because they view it as a complicated machine that could electrocute the untrained. Fear not, because the AED will never shock a healthy heart, and it is as easy to use as 1-2-3: (1.) Press the “On” button, (2.) plug the cord connecting the pads into the AED, and (3.) stick the pads to the victim’s bare chest. The AED will then provide you with voice prompts, instructing you whether the victim’s heart is stopped and if you need to press the “shock” button. That’s all there is to it. Don’t be afraid to act.

Is an AED expensive?

AED units used to cost over $5,000 each, but thanks to the improvements in electronics, software, and mass production, AED units now range in price from only $1,195 to about $2,000. At this price, saving lives becomes affordable.

Why don’t more businesses protect lives with an AED?

If AEDs are so effective, easy to use, and affordable, why don’t more businesses employ an AED? Businesses typically site two reasons why they don’t have an AED on hand and ready to save lives: (1.) lack of training, and (2.) cost. But, we now know that AEDs are easy to use and quite affordable, even to the small business. So let’s start saving lives with AEDs.

Aqua Sports, Inc. “No Excuse AED Policy”
The $1,195 minimum AED retail price still discourages most small businesses from making the commitment to better protect lives. As a result, Aqua Sports, Inc., a Fort Lauderdale, Florida based “Elite SCUBA & Rescue Training Institute” has partnered with to provide AEDs to dive boat operators at no cost. Aqua Sports, Inc. will furnish as many SCUBA day-excursion and live-aboard boats as possible with an AED. Aqua Sports, Inc. provides the AED in exchange for dive services for Aqua Sports, Inc. clients, so the purchaser never has to pay a dollar out of pocket. That’s right. You can put an AED on your dive boat, without paying a single dollar. It is what Aqua Sports, Inc. calls their “No Excuse AED Policy” focused on eliminating the AED purchase price obstacle. Aqua Sports, Inc. has been a leader in the SCUBA & Rescue industry and is committed to saving lives. It has furnished dive boats and live-aboards in New England, Florida, the Florida Keys, California, and the Caribbean. also provides grant and subsidies for businesses that cannot afford an AED. Thanks to Aqua Sports, Inc. and, dive boats and small businesses can no longer claim that obtaining an AED is too expensive.

For more information contact:
Aqua Sports, Inc.
[email protected]

[email protected]

*American Heart Association, 2005 ECC Guidelines

Underwater Photography Frequently Asked Questions

What are all the white spots on my pictures?
The “white spots” or backscatter are caused by the strobe being too closely aligned with the camera/lens. The light from the strobe goes straight out and bounces off particles, dirt and other crud in the water directly back into the lens creating highlights or white reflections off the particles. See the backscatter article in our Lights & Strobes section for more info on the subject.

Keep Reading

Christmas in July

A deep look at new species!
by Richard L. Pyle

Aerial view of the coastline at Christmas Island; the worlds largest coral atoll. Photo: Richard Pyle
The small airport at Christmas Island. Photo: Richard Pyle
This outrigger canoe served us well as a dive platform. Photo: Richard Pyle
Richard Pyle and John Earle carry dive gear to the outrigger canoe dive boat, while Matt Craig looks on. Photo: Brian Greene
John Earle enjoys a moment in the shade as we prepare to launch. Photo: Richard Pyle
Brian Greene inspects the oxygen sensors on his rebreather prior to embarking on a deep dive. Photo: Richard Pyle
Brian Greene ascends from a deep dive at Christmas Island. Photo: Richard Pyle
John Earle captures video of rare fishes 300 feet deep at Christmas Island. Photo: Richard Pyle
John Earle captures video surrounded my massive swarms of cardinalfishes 280 feet deep at Christmas Island. Photo: Richard Pyle
Richard Pyle prepares fish specimens for photography and preservation. Photo: Brian Greene
A batch of fish specimens sorted for photography and preservation. Photo: Richard Pyle

I awoke in my London hotel room sticky with sweat; the mid-July heat mitigated only by an oscillating fan. I pushed aside the mosquito netting that surrounded my bed and glanced outside the window to get a sense for the weather. We had been up late the night before, futzing with our equipment and discussing alternatives for the day’s plan. If conditions were right, we would head for Poland. If the wind was too strong, however, we’d only go as far as Paris. As I watched the treetops sway gently in the light morning breeze against a sunny blue sky, the prospects for Poland seemed good.

But typical of the first day of any expedition of this sort, the last-minute tweaks to our equipment dragged on throughout the morning, delaying our departure significantly. It was after lunchtime before Poland appeared on the horizon, and the afternoon brought with it strengthening winds. We could have pushed it, but it’s never wise to push things this early on in an expedition. So we settled for a spot closer to Paris instead. The entire journey from London to Paris took only 45 minutes. Not bad, really – for an outrigger canoe.

Captain James Cook was far from his home in England on Christmas Eve, 1777, when he encountered a barren island in the central Pacific a few miles north of the Equator. Cook named it Christmas Island, and apparently found it to be a somewhat desolate place, without strong prospects as a commercial port. He had no way of knowing at the time that he had stumbled on the world’s largest coral Atoll (in terms of land area). Over the next two centuries, the island was occupied by various westerners, during which time the four main villages received their names: “London,” “Paris,” “Poland,” and…”Banana.” The island now bears the name “Kiritimati,” and is overseen by the Kiribati government (based in the Gilbert Islands).

I was only thirteen when I first visited Christmas Island – dragged along by my bird-watching parents as part of the inaugural effort to promote eco-tourism. There were no scuba diving facilities back then, but just by snorkeling and wandering around the tide pools in front of the hotel, I immediately fell in love with the place. It had every attribute of a stereotypical tropical island paradise: pristine blue waters, spectacularly colorful tropical fish, acres of coconut trees, mild breezes, and miles and miles of white sand beaches unblemished by human footprints.

In the years that followed, I returned to Christmas Island many times – helping the Waikiki Aquarium capture baby black-tip sharks for display in public Aquariums throughout the world, and also with friends to challenge the unexplored outer reefs on our own. The last of this series of trips was in 1989. By that time, my fascination for discovering new species of fishes on deep coral reefs had led me into deeper waters. On one particularly memorable dive that trip, I descended rapidly down the outer reef slope towards my usual maximum depth of 200 feet. But when I got there, the slope kept on going downward. And so did I.

My corpse may very well have remained there to this day, had a trigger deep within my reptilian brain not issued a survival-mode command: “Enough.” When I stopped to look at my depth gauge, it was literally pegged at 300 feet. As I contemplated the implications of this, the debilitating effects of nitrogen narcosis caught up with my rapid descent. Through an inebriated fog, I could see about fifty feet further down where the slope gave way to a precipitous drop-off, falling vertically into the inky black unknown. Along its crest was a veritable forest of large sea fans and clouds of fish – an ichthyologists’ wet dream. One fish in particular caught my eye – a small pale tilefish with a dark tail that I didn’t recognize. Was it a new species, or was I suffering from narcosis-induced hallucinations? Should I swim down and try to catch it?

“Not today,” came another command from the reptilian brain. “I’ll be back,” was my conscious brain’s reply, and I reluctantly headed up. It was another 20–30 vertical feet of ascending before the needle on my depth gauge finally retreated from its 300-foot peg. After several hours of decompression, I emerged through the surf back onto the beach, wondering if I had really seen a new species of tilefish, and vowing to return some day to find out.

Sixteen years later, that day finally came.

A new species of goby in the genus Coryphopterus, discovered on deep coral reefs at Christmas Island. Photo: Brian Greene
A new species of tilefish first seen by Richard Pyle in 1989, during a deep air dive at Christmas Island. This specimen was captured by Brian Greene. Photo: Brian Greene

Floating in the outrigger canoe off Paris, waiting for the highly improvised rusty old porthole that served as the boat’s anchor to snag the reef, we prepared for our first dive of the expedition. Sponsored by the Association for Marine Exploration, a non-profit organization created specifically to support this kind of research, the trip was supported by funds from General Electric in connection with Esquire magazine’s “Best and Brightest” issue of 2004. Our deep diving team consisted of John Earle, Brian Greene, and myself. John, a retired commercial airline captain who has been scuba diving since the 1950’s, epitomizes the notion of a “renaissance man.” Poet (Princeton, with honors), veteran (pilot for the military during Vietnam), naturalist (both land and sea), scientist (his knowledge of reef fishes would put most Ph.D. ichthyologists to shame), surfer, explorer, philosopher – his intellectual breadth and depth can only be described as humbling. Several years beyond the FAA mandatory retirement age for commercial pilots, John is more active and in better physical shape than most guys one-third his age. Brian grew up at Kwajalein Atoll in the Marshall Islands, and is now finishing his undergraduate studies at the University of Hawai‘i. When he swims side by side with sharks (not an altogether rare occurrence), the sharks are the ones that seem out of their element by comparison. Brian has lived more during his twenty-five years than most people do throughout their entire lifetimes.

 One of many new species of fishes collected during this expedition, this basslet of the genus Liopropoma has also been collected in Palau. Photo: Brian Greene
One of many new species of fishes collected during this expedition, this basslet of the genus Liopropoma has also been collected in Palau. Photo: Brian Greene

For my part, the reckless deep-air diving days are well behind me. At the time of my previous trip to Christmas Island, I had only just begun to look into ways of making these deep exploratory dives less hazardous. Starting in the mid- to late-1980’s, several groups of intrepid divers around the world independently began borrowing techniques from the military and commercial divers – incorporating helium and different ratios of oxygen into our breathing mixtures to eliminate narcosis and reduce decompression times, using multiple large-capacity cylinders and other high-tech gear – to develop a new set of protocols for extending the limits of self-contained diving while simultaneously reducing the risks. From our efforts to share experiences, successes, and failures with each other emerged a new revolution in the recreational diving community, which later came to be known as “Technical Diving.”

The contrast between our high-tech rebreathers and the very low-tech outrigger canoe was stark, to say the least. We were joined in the spacious canoe by Matt Craig, a post-doctoral researcher at the Hawai‘i Institute of Marine Biology who was on a scouting trip for a future expedition, and our guide Danny Donegan, a former high-powered accountant who had turned in his business suit and tie for a wetsuit and a thick album of scuba instructor certifications, and was in Christmas Island to train local divers how not to kill themselves. Matt and Danny constituted our surface-support, ably assisted by two Gilbertese boat handlers.

“When should we expect to see you back?” asked Matt – a standard sort of question in this situation. “About three hours,” I figured, watching the sun creeping towards the western sky. “Since this is our first dive of the trip, we’ll try to keep it simple and easy. We may not even find deep water.” Detailed bathymetry charts of this part of Christmas Island are non-existent, and the only depth-reading device on the vessel was the keen eye of our boat driver looking over the side of the boat through polarized sunglasses.

A few minor technical glitches solved, John and Brian rolled off the boat and headed for the rendezvous point on the bottom, fifty feet below. I was the last over the side, and as I righted myself underwater and the curtain of bubbles lifted, I noticed something flapping just to the left of my peripheral vision. A loose line? A clump of my own hair? No. It was a huge centipede, and it was very clearly (and understandably) pissed off. If there is one thing on this planet that can reduce me instantly to a whimpering child, it is a centipede. And as this one scampered across my breathing hose and up my facemask, a whimpering child I became. John and Brian were waiting for me below, so I allowed myself only a moment to regain composure before descending to join them – all the while thankful that no one can tell when you wet your pants underwater.

We picked a bearing seaward, and the three of us set off swimming to find a drop-off. A few minutes later we were heading down a steep sandy slope, dividing our attention between our rebreathers and the insanely large numbers of fishes that surrounded us. I heard Brian trying to get my attention. Through the somewhat muffled but surprisingly intelligible underwater verbal communication that seasoned rebreather divers are capable of, Brian explained to me that a small Grey Reef Shark had inexplicably bumped him from behind, then took off like a terrified puppy. Moments later, muffled shouts from John alerted us to an adult Marlin swimming overhead. We were only ten minutes into the first dive, and things were already getting exciting.

A new species of sand perch (genus Parapercis) collected by Brian Greene at a depth of 400 feet in Christmas Island. Photo: Brian Greene
A new species of sand perch (genus Parapercis) collected by Brian Greene at a depth of 400 feet in Christmas Island. Photo: Brian Greene
A new species of perchlet of the genus Plectranthias, discovered for the first time during this expedition. This species will be named in honor of Esquire Magazine, who helped sponsor the expedition. Photo: Brian Greene
A new species of perchlet of the genus Plectranthias, discovered for the first time during this expedition. This species will be named in honor of Esquire Magazine, who helped sponsor the expedition. Photo: Brian Greene

But the highlight of the dive came a few minutes later, as we approached a depth of 300 feet. Hovering above their burrows in the sand were several small pale tilefish with dark tails. With helium replacing the mind-muddling nitrogen in my breathing gas, I saw the fish with sober eyes for the first time – and it was, unquestionably, a species new to science. It wasn’t to be our only discovery of the dive. Ten minutes later and sixty feet deeper, we encountered about a dozen triggerfish with bright orange tails that none of us had ever seen before; indeed, no human had ever seen before – yet another brand new species! So magnificent was our dive, that we stayed longer than we originally planned. We finally surfaced four and a half hours later – 90 minutes after Matt began looking for our surface floats, but just in time to watch a beautiful Paris sunset.

A new species of sailfin anthias (genus Rabaulichthys) from the deep reefs of Chirstmas Island; it appears to be the same as a new species first discovered by Brian Greene in the Marshall Islands. Photo: Brian Greene
A new species of sailfin anthias (genus Rabaulichthys) from the deep reefs of Chirstmas Island; it appears to be the same as a new species first discovered by Brian Greene in the Marshall Islands. Photo: Brian Greene
A probable new species of flatfish (Soleidae) collected at 400 feet. Photo: Brian Greene
A probable new species of flatfish (Soleidae) collected at 400 feet. Photo: Brian Greene

Over the past fifteen years, we have dragged our rebreathers and large cylinders of compressed helium all over the Pacific – from the Cook Islands to Papua New Guinea, from Palau to Fiji and American Samoa. Our mission is always the same: explore the habitat below tropical coral reefs in search of new scientific discoveries. Whereas conventional scuba is rarely used by scientists below 150 feet, and almost never below 200 feet, the rich and complex coral-reef environment with their associated diverse communities of life extend down to at least 500 feet in places. Most deep-sea submersibles, designed to withstand thousands of feet of pressure, come with a hefty price tag (upwards of $20-30,000 per day, or more), and have consequently been used almost entirely for exploration at depths much greater than 500 feet. Thus, the deep coral reefs between 200 and 500 feet throughout the world’s tropical seas – an area sometimes referred to as t

A new species of triggerfish collected at 390 feet. New triggerfish species are not often discovered. Photo: Brian Greene
A new species of triggerfish collected at 390 feet. New triggerfish species are not often discovered. Photo: Brian Greene

he coral-reef “twilight zone” – remains almost completely unexplored.

If modern studies of biodiversity have taught us anything, it is that going to a place where no one has ever been before will almost certainly result in the discovery of organisms that no one has ever seen before. Though we weren’t surprised to find new species on the deep coral reefs, we were wholly unprepared for how many were down there. The first clues came during an early deep diving trip to Rarotonga, where a few very short dives revealed more than a dozen highly conspicuous new species. Some of them were quite spectacular: one later sold in the Japanese aquarium trade for about $15,000 each.

As our techniques have improved, so too has our ability to find new species. It wasn’t long before we abandoned simply recording how many we had found (over a hundred and counting), and started measuring the rate of new species per hour of exploration time. We’re now up to eleven new species per hour on average, and on some dives the number is closer to thirty. That’s a new species of fish for every two minutes spent on the bottom. Conservative estimates put the total number of undiscovered deep-reef fishes at around 2,000 to 2,500. Pretty impressive, considering that the world total for all known coral-reef fishes is about 6,000 species.

One of the pitfalls of going where no man has ever gone before is that sometimes when you get there, there’s nothing particularly interesting. As Brian and I continued our 30-minute swim across a barren sandy underwater dessert one day later in the expedition, my optimism for exciting discoveries began to attenuate. Just as we were about to give up, the promise of a deep drop-off appeared at the edge of the suboptimal visibility. Quickening my pace downward ahead of Brian, the bottom started sloping at an ever-increasing incline, and I suddenly descended into air-clear water. Though dimmed to a twilight indigo by the murky layers of water above, I could see hundreds of feet in either direction as magnificent rock buttresses protruded seaward, their crests lined with forests of massive sea fans, atop a seemingly bottomless cliff plunging into black abyssal depths. The hairs on the back of my neck stood erect – not only because of the flashback to my dive sixteen years before, but for another reason as well, as captured by the microphone on my running video camera:

“It’s f—ing cold down here…”
“What’s down there?,” Brian can be heard asking in the background.
“Lots of cold water,” was my snappy reply.

As is often the case, an abrupt transition from murky to clear water is accompanied by an equally abrupt thermocline – a sharp demarcation between two bodies of water of substantially different temperatures. The warmer water is less dense, and floats above the cooler water. I have occasionally experienced thermoclines of 10-15 degrees Fahrenheit over a few feet. But this time, the balmy 85-degree shallow water, in which my t-shirt and swim trunks were ample thermal protection, gave way to water that was in the low- to mid-50s.

Once, while watching a program on the Discovery Channel about mountain climbers ascending some alpine peak, I asked a friend why it was that, in order to be considered an “adventurer,” you had to go some place really cold. I guess I finally earned my adventurer’s stripes on that dive.

But as trite as it may sound, I can honestly say it’s not the “adventure” we’re after in our pursuit of new critters on the deep reefs. The real excitement comes not from fending off the occasional shark, gawking at a passing Marlin, or even the awe-inspiring and never-before-seen undersea vistas. These things can surely get the adrenaline flowing – but they represent only one dimension embodied by the spirit of exploration. The real intellectual excitement comes from observing, for the very first time, a new kind of organism that no human has ever encountered before. One more piece in the almost incomprehensible global biodiversity puzzle. Two hundred and fifty years of careful documentation by generations of scientists has yielded fewer than two million species of living things. Even the most conservative estimates put the total count at several tens of millions. We have barely begun to understand the rich diversity of kin we share this planet with, and the species we know about already are, almost by definition, the easiest to find. We still have a long way to go to document the full extent of Earth’s most precious resource, and we are racing against the clock as global warming and more direct forms of over-exploitation threaten to extinguish what there is before we even get a chance to know it ever existed.