Today was our last full day of diving. We made final measurements and removed all the lines, tags, and other gear that we placed on Conch Reef over the past 10 days. Tomorrow we are allowed a final two-hour clean-up dive, and then must be back at storage depth for 4 hours before decompression begins at 4 PM. Seventeen hours later, we will be at surface pressure inside Aquarius (Aquarius is a decompression chamber.) We get to the "real" surface by locking out from Aquarius into the surrounding water - making a short dive from surface pressure in Aquarius, to the ambient pressure or depth outside of Aquarius, then a two-minute ascent to the "real" surface.

I decided to use the slow lane on the "freeway" today, just to store all the sights in my personal RAM. One of my favorite regulars is a big green turtle that lays in one of the sand channels we cross on the way to the study site. It bears the scars of an old wound, probably caused by an encounter with a propeller. A jagged mass of white tissue has replaced the tail and rear shell, and although the wound seems to be "healing," it can't be very comfortable. The turtle simply stares (or glares) at us when we drop down for a visit and I get the distinct impression that it doesn't like humans much because of its wounds. Can't blame it at all. Getting hit by a careless boater would change anyone's outlook on life.

Among my other favorite residents are a couple of spotted morays, always in the same hole; the noble angel fishes that clearly enjoy knowing they are one of the most beautiful fishes on the reef; the cigar-sized yellowhead jawfishes that hover above small holes in the sand and unfailingly and effortlessly slip tail first into their holes as we pass overhead; the sleek and streamlined sand tilefish which is my choice for an "idealized fish," and the nervous little damselfishes who are either chasing away intruders (including us) or fanatically cleaning debris from their territories. If one had to produce a coral reef equivalent of "The Odd Couple," damselfishes would be Felix and scorpionfishes would be Oscar (they just lay around doing nothing all day long).

But one of the best "shows" begins just as we begin our commute. Because Aquarius is positioned over a sandy area, it serves as a focal point for large schools of baitfish. The constantly morphing schools swirl around the habitat day and night with the same hypnotic motions as the twirling ribbons in rhythmic gymnastics. During the day, the school is "fished" by 20 or so black groupers, who slowly glide around like blimps. Occasionally, one of the blimps will light the afterburner and streak into the school for a quick lunch. The groupers must succeed, because they are fat and healthy. But I have yet to see one actually score a hit. It is a different story at night when snook replace the groupers. Snook are sneaky and fast, and they are frequently successful. They lurk about in the shadows of Aquarius, and then dart into the school to isolate one or two fish from the main school. It all happens too fast for the human eye to follow and our only indication of a successful hit is a small cloud of scales twinkling from the snook's gills. I have spent much time watching the snook-baitfish drama unfold just outside our port windows. It can't be easy to be a baitfish, because their life-long mantra is on the order of: one eye for food and the other to keep from being food! Clearly, baitfishes never die of old age and a "bad-hair" morning means never seeing the sunset.

Inside Aquarius, all of us are showing the effects of diving 7-8 hours a day for 10 consecutive days. Our hands are covered with welts from fire coral, our fingers are swollen from being constantly punctured by sponge spicules (as bad as fiberglass slivers), and our feet are red from chafing by our dives. We are beginning to show signs of mental fatigue, as well. Without mentioning names, one of us spent nearly a minute inserting a leg into the arm of a wetsuit and taking another minute to figure out what was wrong.

Despite these little inconveniences, however, each of us would jump at the chance to use Aquarius again. Aquarius gives marine scientists the priceless "gift of time." Time to make meticulous and careful measurements, time to carefully record observations, time to simply look around with a critical, inquiring, and unfettered mind. The ability to swim around with this degree of freedom is indescribable. Aquarius eliminates the common lament of underwater scientists, "if I only had more time, I could..." Because of programs like Aquarius, marine scientists are beginning to understand the physical and biological characteristics of coral reefs and how the two are connected. Our mission contributes to the growing body of information on coral reef algae. Unraveling coral reef connections takes time, simply because of the spatial and temporal complexities. But conservation managers desperately need the information now, because coral reefs have been seriously damaged in many parts of the world by natural causes, anthropogenic causes, or a combination of both. Aquarius provides a means to acquire knowledge of coral reefs. And as we all know, knowledge is power, and power gets things done. Yes, Aquarius is definitely "worth it."