Meet the Dive Staff
Ali Miller
Partner, Scuba Instructor Trainer, Freediving Instructor Trainer, Kiwi's MomTeaching scuba since 2005 and freediving since 2013
What is your favorite underwater memory? My favorite underwater memory was the first time I found myself surrounded by sharks. It was 2009 and we were the only liveaboard at Roca Partida in the Revillagigedo Islands off of Mexico's Baja California coast. We were on our safety stop and all of a sudden a group of 500 silky sharks came out of the blue and surrounded us in peaceful serenity! I started screaming in joy, so much so my dive buddy had to make sure all was well. The ocean does and always will continue to surprise me at every turn.
What is your favorite thing about teaching diving? The best part of teaching scuba and/or freediving is seeing the happy faces of my students after accomplishment of their first open water dive. Passing on the joy, the love, and the appreciation for the oceans is my passion and is why I have dedicated my life and career to these amazing sports and to the ocean!
Wendelinus Benjamin
Partner, Scuba Instructor Certifier, Rebreather InstructorTeaching since 1997
What is your favorite underwater memory? My favorite underwater memory was swimming underwater with whale sharks in Kalimantan, Indonesia. They came up out of the blue and stayed playing with us a for some time. The mystery of these giant creatures captures my heart, and is on every scuba diver's bucket list!
What is your favorite dive destination and why? Kaimana, Raja Ampat, Indonesia - Located in the center of the coral triangle, Raja Ampat has more biodiversity than any other place in the world. Every dive brings something unexpected. Even for a seasoned diver, I usually see at least one thing I have never seen before underwater when I am diving Kaimana.
Bonnie Sherman
Partner, Scuba Sage & Kiwi's GrandmaWhen and where did you first learn to scuba dive? My first scuba dive was in 1980 in Roatan, when there was one satellite phone and five little trucks on the whole island. During my first certification dive - kneeling on the sand- we were bombarded by hundreds of butterfly fish. During my first night dive, there were so many worms out on the ocean floor, I tried to figure out why the island had so many miles of cable when no one lived there!
What is your favorite underwater memory? I have so many - from the giant potato cod in Australia, to be surrounded by sharks in the Socorro Islands and Cocos Island. Mola mola and giant whale sharks in Galapagos, manta rays in Bora Bora and a coconut octopus hitching a ride with me in Indonesia. By far my best memory ever is diving with my children, Ali and Brittany, for the first time.
Brittany Miller
Partner, Scuba Assistant Instructor, Scuba Sage's MomTeaching since 2012
When and where did you first learn to scuba dive? Scuba is a pre-requisite to be in my family, so as the baby of the family I learned to dive when I was 12. We went to Bonaire for my open water training and my first dive without an instructor was with my mom, dad and sister when they took me out for a night dive in front of our hotel. There were tarpon hunting, using our flashlights for help and they kept bumping in to me, so I spent the entire dive holding my sister's arm for dear life!
What is your favorite underwater memory? I learned to love night diving - My favorite memory underwater was diving at night in the Cocos islands and watching small white tip reef sharks hunt for fish while the large Galapagos sharks were hunting them! What a thrill!
John Sherman
Head Service Technician, Scuba Assistant Instructor Trainer, Adaptive Diving Director & Instructor TrainerTeaching since 2012
When and where did you first learn to scuba dive? As one of my electives my junior year in college, I took scuba diving. A year later I went on my first ocean dive in Cozumel and have been hooked ever since!
What is your favorite thing about teaching diving? Passing on the excitement of scuba to someone else is my favorite part of teaching. It brings joy to me and to my students.
Mariah Conn-Mahlendorf
General Manager, Training Coordinator, Scuba Assistant Instructor TrainerTeaching since 2015
When and where did you first learn to scuba dive? I first learned to dive in Utila Honduras on a Winter break vacation in college. I didn't plan on getting certified, but I fell in love with it right away. I ended up postponing my next semester of college so that I could stay in Utila and work on my Divemaster certification for the next three months.
What is your favorite underwater memory? One of my favorite memories underwater was when I discovered that baby squid are attracted to dive lights at night. I was in Grand Cayman and noticed two little orange translucent blobs about the size of my fingernail swimming towards my dive light. They were so cute and they couldn't get enough of my light! I stayed in the same spot watching them playing in my light for about 15 minutes, giggling into my regulator the whole time.
Christine Bloch
Travel Assistant, Retail CoordinatorWhen and where did you first learn to scuba dive? I became a certified diver in 1998 and did my very first dives in Cozumel. Soon after, I had the opportunity to live in Playa del Carmen, MX for the better part of a year and dove Playa, Akumal and Cozumel every chance I got.
What is your favorite underwater memory? One of my favorite underwater memories is of an experience I had in St. Croix in 2004. Towards the end of one of our last dives of the trip, our group was approached by a small pod of dolphins. They stayed with us for several minutes, playing and circling the divers and seeing what we were about. It was magical and I have never experienced anything quite like it; fortunately there was a videographer diving with us that day and I have the whole thing on video!
Craig Hilton
Extended Range Scuba InstructorTeaching since 2010
When and where did you first learn to scuba dive? My diving career started in 2000, when I was trained by the City of Denver to be a Public Safety Diver. It was only after diving in all the places you would never want to go, that I decided to discover the joys of diving for fun and I have never looked back!
What is your favorite underwater memory? Diving in the Revillagigedo Islands (Socorro Islands) for the first time was life changing. I was surrounded by so many different species of sharks and Giant Mantas on every dive, that I fell in love with the ocean and diving!
Steve Art
Scuba Advanced Open Water InstructorTeaching since 2014
When and where did you first learn to scuba dive? Every day after school, I would go home, grab a bowl of ice-cream and watch Mike Nelson save the world in the TV series Sea Hunt. I knew then that someday I wanted to go where no man has gone before (Oh wait, wrong series!). In 1981 I learned to dive off the shores of Southern California in the waters on Catalina Island.
What is your favorite thing about teaching diving? I really enjoy interacting with each student and getting to know them while guiding them through this marvelous experience. It’s really an insight to see the apprehension of the first night turn into the joy of diving by the end of the last pool session. While I get the opportunity to offer a bit of my knowledge, I too learn something new with each class and each student. Plus, I get to ‘hang out’ with other divers, about the coolest people on the planet.
Ray Brienza
Scuba Assistant Instructor TrainerTeaching since 1984
When and where did you first learn to scuba dive? I tried diving for the first time in Acapulco, Mexico in 1977 and decided to get certified when I was in college in Kansas in 1983. The next year I became an assistant instructor at CSU and have continued to teach ever since!
What is your favorite underwater memory? Diving the Blue Hole in Belize. I saw stalacties and stalagmites in the middle of the ocean as I was surrounded by 7 Hammerhead sharks!
Lauren Camacho
Scuba Open Water Instructor, Mermaid InstructorTeaching since 2023
When and where did you first learn to scuba dive? I started diving in 2013, right here at Denver Divers! I completed my certification dives in San Pedro, Belize, and was hooked from the very first moment.
What is your favorite part about teaching diving? My favorite part of teaching scuba and mermaiding is seeing the progress my students make during their classes. Whether first time mermaids in a Try Mermaid session, or experienced divers in a scuba specialty class, I love it when my students leave more excited, knowledgeable, and skillful than when they walked in. I always strive to give my students instruction they truly connect with on a personal level.
Wayne Dahlberg
Scuba Advanced Open Water InstructorTeaching since 2019
When and where did you first learn to scuba dive? I began my scuba training in 2002 in New Jersey, diving off the Jersey shore, at Dutch Springs quarry in Eastern Pennsylvania, in the Delaware River and at Lake George in Upstate New York. All great training experiences, although I definitely prefer warm, clear water!
What is your favorite underwater memory? My favorite underwater memory is really all the diving I've done with my sons. We all went through certification and advanced training together and it was wonderful watching them progress and gain confidence in their skills. Perhaps the best of the memories is renting a Jeep in Bonaire, picking among the numerous shore dives, and planning/diving together.
Wendy Daniel
Scuba Assistant InstructorTeaching since 2023
When and where did you first learn to scuba dive? I got certified in 1994 through Denver Divers! I went to Belize for my open water dives and was hooked! My kids and boyfriend were also certified through Denver Divers, so we are scuba-diving family!
What is your favorite part about teaching diving? Denver Divers is an integral part of my REEFS program at Kent Denver School. Together we teach our students the joys of scuba diving, the importance of the ocean, and the fragility of this ecosystem. Drawing these connections is my favorite part about teaching scuba.
Mark Dunning
Scuba Open Water InstructorTeaching since 2019
What is your favorite underwater memory? My favorite dive was in 2016 on the western side of the Big Island in Hawaii near Kona. I did a night dive with about two dozen Manta Ray's ranging from 12' to 16'. They are beautiful and magnificent creatures and it was my joy to share their underwater environment with them.
What is your favorite thing about teaching diving? My favorite part is giving something back to the sport that I have participated in for 35 years. I also like to see students learn a new sport and become interested in expanding their knowledge of all that scuba has to offer.
Josh Firster
Scuba Advanced Open Water InstructorTeaching since 2021
When and where did you first learn to scuba dive? In 2004, I began my scuba journey in Lawton, OK, where I earned my first three certifications. What sets my journey apart is that my first 30+ dives took place in challenging man-made lakes and reservoirs, granting me the confidence to explore diverse underwater environments with ease.
What is your favorite underwater memory? One of my most cherished underwater memories was during a recent Denver Adaptive Divers (DAD) program trip to Bonaire. This unforgettable journey included spotting my first seahorse, numerous squid, tarpon hunting at night, and a nesting octopus. In Belize, I observed the fascinating progression of teaching predators like sharks that lionfish are a viable food source. Cenote diving in Playa Del Carmen remains another favorite, with its captivating underwater caves and crystal-clear waters, providing an adventurous and wondrous experience.
David Gilbreth
Dive Master Instructor, Recreational Rebreather InstructorTeaching since 2001
What is your favorite thing about teaching diving? My favorite part of teaching SCUBA is proving it is possible for everyone, especially when you have a personal doubt. Watching the realization in the diver's eyes is the best reward.
What is your favorite dive destination and why? The Solomon Islands haves every aspect of the adventure: Travel, History, unique marine life, local culture, and wonderful people.
Kendyll Gooding
Scuba Dive MasterTeaching since 2023
Bio Coming Soon
John Grubbs
Scuba Open Water InstructorTeaching since 2021
What is your favorite underwater memory? My favorite underwater memory is the 1st time I was able to go diving with my kids. They were 10 and 11 and had just been certified. We went diving at Cabo Pulmo as a family. I still remember the tornadoes of fish around us.
What is your favorite dive destination and why? My favorite dive destination is Cozumel. I love drift diving during the day through the spires of coral reef, and night diving to observe all the octopus out and about.
Donita Hilfinger
Scuba Assistant InstructorTeaching since 2017
When and where did you first learn to scuba dive? I first learned that diving was an option in 2005. I received my open water diver certification in 2005 from Denver Divers. As I gained experience, I realized that I wanted to help others enjoy the experience as well and received my AI certification in 2017.
What is your favorite part about teaching scuba diving? Sharing the joy of diving with others. Helping them to see the fantastic animals and plants that cannot be experienced on land!
Mark Holton
Scuba Advanced Open Water InstructorTeaching since 2017
What is your favorite thing about teaching diving? Helping people overcome anxieties. "On the other side of fear is freedom!"
What is your favorite dive destination and why? I first learned to dive in Koh Tao, Thailand and it will always be my favorite. Easy diving, amazing wildlife, a beautiful setting and wonderful memories.
Matthew Horton
Scuba Open Water InstructorTeaching since 2002
When and where did you first learn to scuba dive? My first dive was when I was 7 yrs old with my uncle who happened to be a Navy Seal. I was hooked, and attained my Junior Open Water Diver as soon as I turned 12 yrs old.
What is your favorite dive destination and why? I enjoy researching all aspects of maritime history and viewing the well preserved artifacts on deep Lake Superior shipwrecks. Yes, I dive with a drysuit and full face mask!
Chris Huth
Scuba Advanced Open Water InstructorTeaching since 2018
What is your favorite underwater memory? Diving in Fakarava, PF with thousands of sharks and amazingly strong currents pushing you 4 miles in one dive. Or the sneaky all pro dives we got to do during covid lockdowns in Honduras where we would decide a depth, time and location to meet and everyone just swims out from their local beach access point and met underwater. spending 2+ hours underwater with just your friends and the ocean is the best.
What is your favorite part about teaching scuba diving? The best part of teaching diving is working with people to help overcome their personal fears and issues. It's very rewarding watching someone adapt and advance their skillset and break through their own mental and physical barriers to experience the joy of diving. The look people give you the first time you take them out over a deep wall drop off is also very rewarding.
Ted Kays
Scuba Advanced Open Water InstructorTeaching since 2017
What is your favorite thing about teaching diving? I enjoy having the opportunity to work with a diverse group of students who are excited to learn about and experience a new part of their world. I re-live my own personal experience with each class.
What is your favorite dive destination and why? Lembeh Strait in North Sulawesi, Indonesia is biologically and culturally fascinating!
Adam Knudson
Scuba Advanced Open Water Instructor, Freediving InstructorTeaching since 2013
What is your favorite part about teaching diving? I've worked lots of students over the years in both scuba and freediving. Its an absolute joy to see students fall in love with the ocean and immerse themselves in experiences using some of the skills I taught them. I take a lot of pride in what I do and its an honor to share these gifts with people and add to this amazing community of Colorado Divers.
What is your favorite dive destination and why? Scuba Diving: Sulawesi, Indonesia specifically the Minahasa Peninsula region. The area sits right in the middle of the coral triangle and so the biodiversity is insane. Vastly different reefs systems can be experienced from a relatively short boat ride. Its dive trips within a dive trip :). For freediving, I think the Sea of Cortez is amazing! You can get close to very large animals and their massive congregations on a good breath hold and fins!
Devon Knudson
Scuba Assistant Instructor, Assistant Freediving InstructorTeaching since 2013
Bio coming soon
Kara Leach
Scuba Assistant InstructorTeaching since 2021
What is your favorite dive destination and why? Caves in Playa del Carmen- beautiful, challenging, peaceful, zen-like
Helping people be safe to have their own fantastic adventures
Rae Lewark
Advanced Freediving Instructor, Mermaid InstructorTeaching since 2022
What is your favorite underwater memory? My favorite underwater memory is freediving with Galapagos sharks off the North Shore of Oahu.
What is your favorite part about teaching freediving? My favorite part about teaching freediving is showing people how incredible the human body is in the water and how naturally we can interact with the underwater world.
Sandy Martin
Scuba Assistant InstructorTeaching since 2010
When and where did you first learn to scuba dive? I took the class/pool portion of open water diver training at our very own Denver Divers in 2000, then completed my certification dives in the Florida Keys a month later.
What is your favorite underwater memory? So many favorites-- life under the sea is just amazing! It could have been the fleeting visit by a pair of sailfish, coming face to face with a young mola mola, finding a tiny seahorse, watching cuttlefish flash their colors, swimming through an endless school of salema, or seeing coral spawn.
Drew Mayers
Scuba Open Water Instructor, Training SpecialistTeaching since 2019
What is your favorite thing about teaching diving? I have always had a passion teaching. I enjoy teaching beginners to experienced divers new skills so they are safe and comfortable in the water. I actually started diving with Denver Divers in 1993 and decided to become an instructor to pass my passion along to all future divers!
What is your favorite underwater memory? I love all types of diving experiencing the under water world. The most memorable experience was my first open water dive in Hawaii where I dropped in on a school of Tiger Sharks during a drift dive.
Britni Minichino-Sikora
Scuba Open Water Instructor, Training SpecialistTeaching since 2019
What is your favorite underwater memory? I really enjoy swim-throughs. It doesn't matter where I am diving, if there is one, I am usually going through it. Taking my time, I love observing the different formations and colors of the rock and coral. And you cannot forget the marine life that calls it home.
What is your favorite thing about teaching diving? It is truly rewarding watching students overcome their initial fear they may come in with and become confident divers. Watching students become comfortable in their skills, water, and environment is pretty awesome to see.
Joan Nash
Scuba Assistant InstructorTeaching since 2023
What is your favorite underwater memory? Being underwater and swimming with the marine life in their own habitat is without doubt my "Happy Place". One of my favorite underwater memories was in Belize, when a family of dolphins took interest in our group and actively engaged playfully with us. To see and be so close to theses animals was amazing!
What is your favorite destination and why? I have been very fortunate to be able to travel to a variety of different locations worldwide to dive. When asked about my Favorite destination, I often will reply "Wherever I happen to be at the time". A bit vague, but true. The beauty, serenity and wide variety of marine life we see is always captivating, from the golden grouper in Cabo Pulmo, to the soft coral walls in Fiji, the stunning cardinal fish, the giant frog fish and pristine coral reefs in Indonesia or the Giant Manta rays in the Maldives, I absolutely love them all! Each environment is so unique and special in it's own way.
Harris Neil
Scuba Assistant Instructor TrainerTeaching since 2013
What is your favorite underwater memory? Being with friends when special things happen, like encountering dolphins, octopus, or the other sea life you only get to see on rare occasions.
What is your favorite dive destination and why? As soon I think one place is a "favorite", I have a great day at another. I don't have a favorite, but I'm continuing the search.
Judi Persoff
Scuba Assistant InstructorTeaching since 2008
What is your favorite thing about teaching diving? Seeing students become comfortable with the gear and enjoying the new sport.
What is your favorite dive destination and why? I loved Palau! It was challenging but doable and the marine life was spectacular with lots of things not seen in the Caribbean: bump head parrot fish, Napoleon Wrasse, mandarin fish, and cardinal fish. Amazing!
Vincent Phelan
Scuba Advanced Open Water InstructorTeaching since 1991
What is your favorite underwater memory? Every dive with my family is the best and builds lifetime memories!
What is your favorite dive destination and why? Galapagos Islands! The diverse and unique sea life that can be encountered!
John Route
Scuba Assistant Instructor TrainerTeaching since 1997
What is your favorite thing about teaching diving? Having a difficult student that you get certified and then see them on a Denver Divers group trip.
What is your favorite dive destination and why? Indonesia and Palau - diving with my favorite dive buddies!
Allie Schetrom
Freediving Assistant Instructor, Mermaid InstructorTeaching since 2022
Bio Coming Soon
Leif Skaar
Scuba Assistant Instructor TrainerTeaching since 2003
What is your favorite underwater memory? As a technical diving instructor, I am certified to dive below 330 feet. When in Chuuk Lagoon, I was able to dive the sunken Japanese ships and put these skills to the test. Seeing Jungle tanks sitting on the deck of the "San Frasco Maru" at 170 feet, sitting there since 1944 was a pretty spectacular moment.
What is your favorite dive destination and why? Anywhere in the South Pacific: Reefs in Papua New Guinea, diving the Evil Trench in Fiji and the WWII history of Palau. And of course, Truk lagoon now called Chuuk Lagoon.
Cody Spangler
Scuba Assistant InstructorTeaching since 2023
Bio Coming Soon
Christine Swenson
Scuba Open Water InstructorTeaching since 2023
What is your favorite underwater memory? My favorite underwater memory is doing a night dive in Hol Chan Marine Park in Belize. The reef was so active that night. I saw three octopus, a moray eel hunt and eat its prey, and lots of rays. It was amazing. Everywhere I looked there was something amazing to see.
What is your favorite dive destination and why? For now, the West End, Roatan, Honduras. The marine park does an excellent job with the reef, the research they are doing is interesting and seems to be working, the people are fantastic, and the dive sites are very close by.
Lin Szydlo
Scuba Assistant InstructorTeaching since 2007
What is your favorite thing about teaching diving? That moment when an apprehensive student gets it and their face breaks out in an immense smile.
What is your favorite dive destination and why? Cabo Pulmo, Mexico! The health of the marine park just gets better and better. Jacks, mobula rays, bull sharks and smiling puffers are just some of the critters. The small eco lodge is comfortable, relaxing and a great escape. The people are kind and fun.
Ingrid Underwood
Scuba Assistant InstructorTeaching since 2020
When and where did you first learn to scuba dive? I learned to scuba dive with Denver Divers in 2014; then kept returning for additional classes and adventures.
What is your favorite underwater memory? Initially, it was my first open water dive in Italy where I was introduced to my diving obsession. However, surfing the strong currents of Raja Ampat, Indonesia with eleven manta rays for thirty minutes pretty much sums up the best dive ever! I enjoy identifying marine life and am always searching for octopus, cetaceans, seahorses, frogfish, batfish and sharks.
Trevor Updegraff
Freediving Instructor, Scuba Assistant Instructor, Kiwi's DadTeaching since 2020
When and where did you first learn to dive? I fell in love with snorkeling as a kid and started scuba diving with my family at twelve years old. But I first learned freediving techniques living in Hawaii after college and was drawn to the purity of the sport.
What is your favorite dive destination and why? Though hard to compare with the teeming reefs of Indonesia or magic of the Galapagos, my favorite still has to be Cozumel for its crystal clear waters, spectacular reef structures, and so many great memories.
James Vanselow
Scuba Open Water Instructor, Training SpecialistTeaching since 2019
What is your favorite underwater memory? Having a Green Sea Turtle swim right up to me on the Benwood wreck in Key Largo, FL
What is your favorite thing about teaching diving? Getting to do something I love!
Rito Vasquez
Scuba Open Water InstructorTeaching since 2023
When and where did you first learn to scuba dive? I visited Oahu, Hawaii in December of 2010 and did my open water dives at Turtle Canyon and Koko Craters. A beautiful place up the coast from Waikiki and a place where you can see the state's most recognized landmark, Mount Leahi, better known as Diamond Head. In high school, I had several friends who visited Hawaii to swim with turtles and I always knew my day would come! It was amazing!
What is your favorite underwater memory? On a birthday trip with friends to Mahahual, Mexico we were beginning our ascent to end our dive, when a group of dolphins came from the blue and began playfully circling around us for several minutes. This is the sort of unexpected magic you always hope for but can never predict.
Blair Whitaker
Freediving InstructorTeaching since 2019
What is your favorite underwater memory? My first freedive to 100 feet and freediving the swim-throughs at Devil's Grotto in Grand Cayman!
What is your favorite dive destination and why? My favorite place to freedive is in the cenotes of the Yucatan Peninsula in Mexico. With over 100' of visibility and bright sunbeams, its visually stunning!
Sterling Wind
Scuba Assistant InstructorTeaching since 2022
I grew up in S. California, and I learned to snorkel shortly after I learned to swim around the age of six or seven. I have always loved the water, and from an early age, I knew that one day I would become a scuba diver. Little did I know that I'd have to relocate to Colorado and wait for another 15-years before walking into Denver Divers in 2003 to train and earn my scuba c-card finally.
What is your favorite dive destination and why? I've been lucky to dive in some incredible fresh and saltwater dive sites in Iceland, around the Pacific Ocean, the Caribbean, the Sea of Cortez, and the Atlantic Ocean. I can honestly say that my favorite dive destination is my next. Let's go diving!