Blue Grotto

“Dive more, post less”

– motto of Amigos Dive Center, in north-central Florida

Blue Grotto could be in a storybook. The heroes would arrive at the freshwater spring after a long, arduous journey through the north Floridian wilderness, drenched in sweat, thirsty, and tired. They would trudge along with their heavy packs and round a bend in the dusty trail, then find themselves facing an unimaginable oasis. The circular basin is filled with crystal-clear water, unencumbered by algae or silt. The glassy surface is disturbed only by sprinkles from the miniature waterfall above. Bluegill sunfish glide around in the upper layers, while a turtle named Virgil paddles lazily below.

In reality, Blue Grotto is surrounded by a busy park with picnic tables and vans full of college kids, but its beauty was not lost on me. It was a perfect dive site to learn new skills.

I’ve spent the last week in north-central Florida, a part of the world that divers simply call “cave country.” Thousands of freshwater springs fill basins in the limestone aquifer, producing ideal sites for SCUBA diving at all levels. I came here to build up my technical diving skills and learn how to use a closed-circuit rebreather.

Most SCUBA diving is “open-circuit,” which means the diver carries a tank of compressed gas on their back, which they inhale, and when they exhale, large bubbles rise to the surface. This system is actually very inefficient, because humans only metabolize a small percentage of the oxygen they breathe. Rebreathers capture the exhaled gas and remove CO₂ to recycle the diver’s breath. By diving closed-circuit systems, divers can stay deeper longer, while accumulating less decompression obligation. This means I’ll be able to spend more of my dive time on the seafloor and less of it up in the water column, just waiting for compressed gases to flush out of my system. (Mom, if you’re reading this, that means rebreathers are safer.)

Diving closed-circuit is not without its challenges, though. On open-circuit SCUBA, you can fine-tune your buoyancy in the water column by simply breathing in or out. Inhale, and you float up just a little bit, exhale, and you float down. I learned this skill very well on my first trip to theCaribbean, and used it to view coral reefs close-up without contacting them. On a rebreather, though, my exhaled breath goes into a counter-lung, not the surrounding water column, so the gas volume in the system is more or less constant at a given depth. Instead of using my breath to fine-tune my buoyancy, I had to learn to manage the 8.5 L gas volume in my breathing loop to make sure it didn’t expand or shrink too much as I changed depth. Technical diving is an exercise in extreme multi-tasking, but I felt by the end of the week that I had gotten the hang of it.

There was one dive when my instructor and I surfaced in Blue Grotto to find Virgil the turtle resting on the dive platform. While waiting for him to move out of the way, we floated on the surface and became the landing pad for two dragonflies. It was this beautiful moment that reminded me why I dive: to get out into nature and experience the aquatic world first-hand. I’m glad I got to do that at Blue Grotto.

In case you’re wondering, my instructor, Rob McGann, has been exceptional. He worked with the skills I had coming in, moved at my pace, and helped me become an all-around better diver. If you’re looking for an instructor or guide in cave country, I highly recommend Dive With Rob.