So what's the coolest thing you've seen down there?

Pose that question to veteran Charleston scuba diver Sally Robinson, and just sit back and enjoy. She'll fire off story after story about incredible underwater encounters with spotted dolphins, other-wordly views of shipwrecks, and run-ins with unbelievably big Goliath grouper "” all in waters off Charleston.

Robinson and husband Tom own Charleston Scuba, one of the area's best-known dive shops. Since being certified in 1986, Robinson has earned the credentials to train not only divers, but also other instructors. Over the years she's explored the clear blue waters of the Caribbean and visited countless tropical reefs and wrecks. But her favorite place to dive, she says, is right here at home.

"I always know I'm going to see something different," she says. "It's like going on safari. Something always comes around the corner, it's always something new."

Indeed, though Charleston lacks the crystal-clear water and shallow-water coral reefs found in tropical locales, our blue offshore waters feature one undeniable attraction: huge fish, and lots of them. The wildlife swimming 20 or 30 miles off Charleston "” and sheer size of some specimens "” is what keeps veteran divers excited about diving here at home.

Take Robinson's trip to the Indigo Ledges, a natural reef line in 70 to 80 feet of water. She and a diving buddy were exploring the bottom when they looked up and saw a phalanx of cobia swimming toward them, about 24 of the big brown fish.

"When we see cobia, they're usually following something big, and it's almost always a big stingray," Robinson says. "Stingrays are very cool, and there are very large ones off Charleston. They're called rough-tail stingrays, and the females are immense. They are 6 feet wide, at least. "¦ Their tails are as thick as your arm and their eyes are as big as golf balls.

"So we see these cobia, and then she comes along, like the mother ship."

Amazed at the sheer size of the stingray looming out of the darkness, Robinson and her diving buddy sat stunned as the gigantic animal cruised by.

"She goes off into the distance, and then we see her double back. The cobia are outraged, they're all in disarray. She does a complete back flip, comes swimming back, makes another flip and comes right beside us, where we're kneeling in the sand."

As her entourage of confused cobia lingered nearby, the big ray settled in the sand and "switched her eyes over at us."

"I just look at her, going, "Wow!

""¦ I don't how much of a brain they have, but what animal would do that if they weren't interested in seeing you? Making a double flip, a double U-turn, to come right back next to you?

"It was one of the coolest thing I've ever seen."

Lowcountry diving

Mention scuba diving to most Lowcountry folks, and they'll most likely think of tropical destinations. But Charleston has tight-knit community of divers, and many practice their passion right here at home.

Diving off Charleston does present unique challenges. The water is, indeed, murkier than you'd find in much of the Caribbean Sea, so divers must often travel at least 15 or so miles offshore to find workable water clarity. But veteran divers say the payoffs are huge. The many shipwrecks and natural reefs off our coast are loaded with abundant animal life, and there's often the chance that a diver is visiting a place no human has ever seen.

There are plenty of other reasons to head under the waves, and the world of Lowcountry diving spans a few distinct categories:

  • Recreational diving, in which people visit offshore wrecks and reefs, where the open ocean water is clear, for the sheer fun of exploration and for underwater photography.
  • Spearfishing, an intense and productive sport that appears to be growing in popularity.
  • Commercial diving, which includes military applications, scientific endeavors and marine construction and maintenance.
  • Relic and fossil hunting, in which divers crawl along the bottom of inshore waterways such as the Cooper River, hunting archeological relics and prehistoric sharks' teeth.
  • Though many divers are active across these categories, most fall into two basic camps: recreational divers who want to simply observe underwater wildlife, and speargunners who want to do that, too, but also take home dinner. Beginning divers should keep in mind that some tension exists between the recreational diving and speargunning camps. Some divers say spearfishing strips underwater habitats of wildlife. Most speargunners say such fears are overblown.

Charleston is home to two major dive shops, Charleston Scuba in West Ashley, which caters to recreational divers, and Lowcountry Scuba in Mount Pleasant, which caters to spearfishing enthusiasts.

Robinson says the recreational diving community is definitely growing, and she's been signing up more beginners for certification classes over the past few years. These newbies range from junior high-schoolers to senior citizens. Robinson also sees a definite increase in women taking up the sport, and has noticed a spike in those interested in underwater photography.

Spearfishing has also fueled the growing interest in scuba diving. Pictures of local divers holding huge grouper, snapper and even lobster have flittered across cyberspace for a few years, catching the attention of many traditional rod-and-reel fishermen.

Jason Ward, a 33-year-old West Ashley resident who grew up hunting and fishing, is one of the area's spearfishing converts.

Ward, who's also an offshore trolling aficionado, began diving and spearfishing in 2003. He now completes 40 to 50 dives per year, usually three or five dives every time he goes out. Like most speargunners, Ward concentrates his efforts fairly far offshore, in prime bottom-fish hunting grounds under 80 to 120 feet of water.

For Ward, bagging big grouper and tasty lobster is nice, but it's the sense of exploration that really keeps him heading out from Charleston with his boat loaded with scuba tanks.

"Every single spot has its own characteristics, as far as what the structure looks like and what type of fish are down there," Ward says.

Since getting hooked on scuba, Ward has dived in the Bahamas, Mexico, Hawaii and the Florida Keys. He, too, says diving off Charleston is something special.

"I would say our structure is similar to some of the stuff you'd see in the Florida Keys," he says. "The thing that you lose in Charleston is because we're diving at deeper depths, you don't get the same amount of light down there. So you're not seeing the beautiful reds and oranges and browns. If you didn't know what it was down there, you'd just assume that all this coral was just a pale green color.

"But as far as the fishing is concerned, hands down Charleston has got the big grouper and snapper compared to these other places. I dove in Hawaii, and they've got these neat structures, with caves and overhangs ... but all the fish are little.

"Charleston's got it going on."

Ward says offshore divers will usually see familiar bottom-fish species such as gag grouper, red grouper, scamp grouper, red and vermilion snapper, red porgy, black seabass, triggerfish, amberjack, spadefish, flounder and sheepshead.

But divers will also get to see the animals that most anglers don't catch huge spotted eagle rays, blue spotted coronetfish, hogfish, wrasses, squirrelfish, bigeye snapper, flying gurnards, hakes, tautog, moray eels and even lobsters.

Divers will also run into massive schools of bait fish, an impressive sight for anyone who hasn't seen it before.

"Sometimes, these schools of cigar minnows are probably tens of thousands, if not hundreds of thousands, of fish," he says. "Sometimes, the bait will surround you so thick, just inches from your mask, that it's very hard to see anything, or you start seeing double.

"I've had to abandon dives before because I started seeing blurred vision and feeling the onset of vertigo from being surrounded by thousands of little swimming fish."

How far can you see?

A common misconception about diving off Charleston is that the water clarity is too poor for it to be much fun.

Robinson had the same reservations the first time her husband offered to take her diving offshore Charleston.

"I grew up going to Sullivan's Island in the summers, and you can't see your feet when you're up to your knees," she says. "I really didn't believe him when he said how pretty it was.

"I remember the first time he took me out to the Freddy Day wreck, it was late April or early May. I got down there and it was so blue my eyes about popped out of my head. I just couldn't believe it. I think I was hooked at that time on offshore Charleston. It was just so different than what I thought it was going to be, and there were just fish everywhere."

According to Ward, divers heading down in 100 feet of water can usually hope for a visibility range of 30 to 60 feet. Most divers feel comfortable with 25 feet or better of visibility; anything less than that makes navigation and spearfishing more difficult, he says.

Murkiness, however, is also the key to the amazing amount of life off the Lowcountry coast. Tropical waters are crystal clear because they don't carry the algae and plankton needed to support a rich marine ecosystem. Charleston's waterways, on the other hand, are a stew of nutrients and microscopic life.

Many factors affect just how cloudy the waters off Charleston become depth, current, tidal stage and the presence of storms are a few. Ward says that in waters 60 feet or less in depth, tidal currents play a greater role in visibility. When an ebbing tide pushes dirtier inshore waters further offshore, visibility drops off quickly. At a peak high tide, though, visibility at these nearshore spots is much better.

But Ward says the main driver of water clarity seems to be time of year. "Visibility is typically best in the cooler months and worst in the heat of the summer. In this area, we seem to have a seasonal bloom of plankton and algae which tend to greatly reduce visibility. Usually the water starts to clean up in the fall and stay pretty clear until the late spring.

"I remember diving the Comanche Wreck several years ago in October and looking at my dive computer which said that I was at 108 feet. I looked up and could see the ripples on the surface and the sun. That's pretty clear water.

"On the other hand, in the heat of the summer mixed with a decent current, I've seen visibility as bad as 5 feet."

Robinson says June and early July are great times to find good visibility off Charleston. May's also very good, she says, if the winds calm down.

"May can be beautiful, I mean stunning. That's probably the best time to do the Freddy Day wreck.

"And the nice thing about the end of May and the first of June is that's when you see all the critters moving back and forth. That's when I've seen leatherbacks (turtles), sunfish, manta rays, a lot of shark."

Where to go

Divers with basic open water certification are restricted to relatively shallow water but can still visit a variety of dive spots in 40 to 60 feet of water. Some of the most popular and well-known spots in this range are the Frederick W. Day wreck, the Anchor Ledges and the Charleston 60 artificial reef.

The "Freddy Day" is a wooden schooner that sank off Charleston in 1914. The ship was loaded with bags of cement, and over the decades those bags formed a reef about 200 feet long. The top of the reef is about 40 feet under water and the bottom is at 54 feet.

The Anchor Ledges are at 60 feet just a short distance from the Freddy Day. "The Anchor Ledges are very good," Robinson says. "It's very cool looking, with big schools of baitfish that go from the bottom to the top. It's got a nine-foot nurse shark on it. "¦ We've seen big sandtigers on there, which are snarly-looking but pretty benign."

The Charleston 60 artificial reef is also in 60 feet of water, and includes a large sunken barge and other structures. "The Sixty" is one of Charleston's most well-known nearshore fishing spots.

Divers with advanced open water certification tend to venture out a little further, where they'll find a wider range of bottom-dwelling creatures in clearer water. Many of these deeper spots are artificial reefs, large ships intentionally sent to the bottom to form reefs.

Two of the most popular are the Comanche, a 165-foot long former Coast Guard icebreaker and Y-73, a 180-foot tanker. Y-73 is in 100 feet of water. Its main deck is at 80 feet and the top of its bridge is at 65 feet. The Comanche wreck is slightly deeper, with a main deck at about 93 feet and a smokestack rising to about 75 feet. The bottom of the Comanche, where the sunken vessel wallowed a hole in the sand, is about 115 feet.

"Everybody wants to do the big wrecks, and the big wrecks are great," Robinson says. "Y-73 is probably one of the nicer wrecks to do. It's still in good shape, it's got a lot of profile and there are lots of fish that move in and out. There's a lot of big grouper on there, big spadefish "” really big spadefish "” and really big amberjack It's just a really nice, good-looking wreck. And it's very photogenic.

"The other wreck that people really like is Comanche, for the same reasons. It's in deeper water, and you really feel like you're out there, cause you are. You're 35 miles out from the jetties. It's very blue, and you usually see all kinds of weird stuff. We've even seen Goliath grouper there, really big ones."

Such well-known reefs and wrecks draw crowds of not only divers, but also fishermen. For this reason, Ward prefers to dive down to smaller, relatively unknown spots, where spearfishing opportunities are better.

"I have coordinates to a 25-foot long boat sticking 3 feet out of the sand that carries a higher biomass of grouper, snapper and trigger fish than any vessel at the Y-73 or the 165-foot-long Comanche (sunken Coast Guard cutter)," Ward says.

Ward says most experienced spearfishermen prefer hunting "live bottom," rather than the big wrecks and reefs. Of course, finding such areas is easier said than done. Most of the ocean bottom off South Carolina is covered with sand. Rod-and-reel anglers, spearfishermen and recreational divers all look for live bottom areas that concentrate fish.

Ward says these isolated areas can range in size from a half-acre to several acres, and generally fall into one of a few categories:

w Ledges and rock outcrops, which are usually found inshore of the continental shelf. The natural formation are typically between 2 and 15 feet tall, with many in the 3- to 7-foot range.

w Flat, hard bottoms, with smooth stone covered in a thin layer of sand. Sometimes these areas have just enough rock or sponges sticking up to hold fish at certain times of the year.

w Low- to medium-relief coral formations. These "patch reefs" range in height from just a few inches to 8 feet, and are prime habitat for most bottom species, including lobsters.

w High-relief natural structures, which are found in much deeper water around the continental shelf. Many of these areas, like Georgetown Hole and Edisto Banks, are too deep for most divers.

Getting started

Like most other water-related pursuits, diving can be expensive. Most beginners spend about $800 to get certified as an open water diver, which includes the cost of training, multiple check-out dives and snorkeling gear. After that, divers can easily spend another $1,200 to $2,000 outfitting themselves with basic gear such as a wet suit, dive computer, regulator and buoyancy control devices (BCDs).

Many divers rent their tanks, which saves them from costly but critical maintenance requirements.

Ward says most spearfishermen in Charleston invest in further training to become certified advanced open water divers and enriched air (Nitrox) divers. This training enables them to safely dive deeper, stay at the bottom longer and reduce the time spent waiting between dives.

Ward says diving off Charleston is well worth the time and financial investment.

"The first time I dove on a live bottom, I thought, God, I wish I had done this 15 years ago."

Contact Matt Winter, Tideline senior editor, at 843-834-3762 or matt@tidelinemagazine.com.