Mention Belize and “blue” is the word that springs to mind for most divers thanks to the world-famous Great Blue Hole. But I think of purple. The regal hue permeated my first dive on the world’s second-largest barrier reef: purple queen parrotfish swimming, purple tube sponges soaring, purple sea fans sprawling. Minute purple creole wrasse flapped iridescent while fairy bassets with purple heads and simmering yellow tails set the water aflame. Small purple specks not pictured on either of my fish slates flickered all around, and even the blue chromis looked purple as they streamed in scaled rivers.

As I discovered during my week aboard Belize Aggressor IV, there’s so much to Belize when you look beyond the blue.

1. Half Moon Caye Wall

Half Moon Caye is a natural monument and part of the Belize Barrier Reef Reserve System, a UNESCO World Heritage Site. On one side of this wall site, the open ocean offers the chance to encounter pacing blacktip reef sharks. Don’t wear anything shiny; barracuda like this site as well.

On your other side, the wall is bustling with life: four-eyed butterflyfish, parrotfish, trumpetfish, rock beauties, fairy bassets and garden eels can all be spotted. During your safety stop, keep your eyes peeled for southern stingrays shuttling through the sea-grass meadows past the reef.

2. Long Caye Ridge

This is a prime night splash. Caribbean reef squid are “everywhere” at this reef, says Aggressor Captain Shea Markwell. During my dive here, I met no fewer than 10 of these conical beauties. The second squadron my buddy and I encountered consisted of seven squid, one of which was chowing down on a small silver fish. We followed the group down to 70 feet, enraptured, refusing to end the encounter until he finished dinner. This dive offered a plethora of other great spots—ghostfish, banded shrimp, Caribbean reef octopuses, hordes of jackfish and scads of tarpon—but iridescent squid squads will always take the cake for me.

LOCAL DIVER TIP: Keep an eye out for the resident yellow seahorse at Cathedral, a site in Lighthouse Reef!

3. Tarpon Cave

In addition to great pelagic encounters to be had at this wall—from reef sharks to eagle rays and hawksbill turtles—a distinct coral cut-through puts this site on the map. (It’s easy to miss, so ask your divemaster to point it out to you.) Called the Chimney, you drop down through stacks of coral like a bubbly London sweep until you near the sand. Despite the name it is not an overhead environment. At the sand, an arc appears that spits you off the wall in glorious fashion. Plan on a deep dive if you’re going down and out: My computer read 93 feet as I finned off. In addition, get ready for very friendly animal life at this site. Groupers are omnipresent along Belizean reefs, but my group found these to be particularly prone to following us around like puppies.

4. Painted Wall

This site is named so for the painted tunicates, iridescent baubles crowned in purple fringe my group spotted a good 90 feet down. A biodiverse dive, it can deliver whether you’re looking for macro, mega or enough fish to fill an aquarium. Ghostfish, squirrelfish, angelfish, black durgons, baby butterflyfish, rainbow parrotfish, banded butterflyfish, smooth trunkfish, crabs, arrow blennies, roughead blennies, bicolor damselfish, angelfish, blue chromis, a juvenile nurse shark—the list of encounters from my liveaboard group could go on and on.

5. Chain Wall

There’s one word for this site: sharks. I also saw an eagle ray, turtle, and two dolphins on one dive, but the sharks here are so predictably friendly Aggressor first mate and divemaster John Garraway said during the dive briefing to expect interactive sharks.

Sure enough, a Caribbean reef shark was the first thing I saw dropping into the water and the last thing I saw hanging from the safety stop bar below the boat. For the hour in between, three reef sharks fanned out along the sea-grass meadow, cut through the group on the reef and swam between us along the wall. Keep your head on a swivel!