Inside Angles: Tank Times—Antics of Our Finned Friends

One of the more enlightening opportunities I have had over the last 40 years has been having access to a 2,500-gallon aquarium—we call it simply “the tank”— in which to hold, photograph, and watch fish. The tank in our current “tank room,” has 2-inch-thick plated glass embedded in concrete. It cost $69,000 to build in 1998, when we moved into our present location on the banks of the Upper Mississippi River at Baxter, Minnesota.

Early on, by about 1983, we were intent on doing pioneering work with underwater photography to use in In-Fisherman magazine. Our first attempts to photograph fish underwater were with scuba gear and early-day Nikonos cameras, which were a modest design improvement in the underwater cameras first developed by Jacques Cousteau. It was slow work and that type of shooting lacked the control to get specific photography to illustrate articles in relatively short order.

Thus, a tank was designed so that dedicated sets could be built in the tank to illustrate specific underwater situations. So, if we wanted to shoot fish along a rock drop-off, we drained the tank and built the rock drop-off on a sand bottom. Then we filled the tank and added the appropriate fish, so the photographer could sit strategically outside the tank, clicking away as the fish did their thing—lights, camera, action. This, too, was time consuming, but it was a vast improvement over diving. And, in the beginning, no one else had access to this type of photography.

I could go on about all the various types of underwater photography we did, but I suppose you get the idea. As I mentioned, though, incidental to getting the photos we needed, we also often had fish of all sorts in the tank for extended periods. The tank was big enough—5.5 feet across the front; 9 feet long; 10 feet wide in the back; and 6.5 feet deep—and had an exceptional circulation and filtration system so that many fish felt right at home.

But not all of them. It was apparent, for example, that walleyes from our natural lakes had a difficult time making the adjustment to tank life. In contrast, most walleyes from the Mississippi River made the adjustment almost instantaneously. Put them in one day and they usually were chowing happily on minnows the next. (Minnows for nothing and an environment without current for free!)

One of the more personable fish species in a general sense is the smallmouth bass. They are highly curious and very tank adaptable—to the point that they usually outcompete fish like largemouths and walleyes and panfish if they are in the tank at the same time. They can be feisty dudes, too—outright bullies at times.

One memorable fish was a river smallmouth of about 4 pounds I added to a tank environment already stocked with several smallmouths, crappies, and bluegills. When I came back to check the tank about 3 hours later, that smallmouth had all the other fish corralled into one of the upper corners of the tank like a sheep dog herding his flock. The only fish that smallmouth got along with was itself. And we more commonly saw that kind of aggression with smallmouths than just about any other fish species.

Except for one blue catfish we kept for about 4 months. No other fish were safe in the tank with that fish, save for, by coincidence, a 10-pound sheepshead that was already at home in the tank when we added the 20-pound blue cat. They soon became buddies and would often rest suspended in mid-tank, facing forward, close enough to be touching.

I noticed over the years that most fish resting in the tank usually faced the front of the tank. My conclusion was that that’s where the action was outside the tank. We were watching them. But they were also watching us.

The blue cat was a graceful and athletic fish. He would play by positioning himself along the lower right side of the tank, close to the middle along the bottom. Then, with precision choreographed elegance he would sweep to the left along the bottom, turn upward and do a half roll that would bring him almost at the surface in the back corner of the tank—then without slowing down he would roll again left and downward and come to a stop in the same position as he had started. Then he might do it again—while the sheepshead finned calmly in mid-tank. A performance for his buddy?

A quick list of the fish we had in the tank over the years goes about like this: brook, rainbow, and brown trout; burbot, madtom, and stone cat; channel cat, blue cat, flathead; brown, black, and yellow bullhead; walleye, pike, muskie; common carp, sheepshead, and lake sturgeon; largemouth bass and smallmouth; striper, wiper, and white bass; bluegills, pumpkinseeds, crappies, and perch; and various redhorse and bowfin.

Stone cats and madtoms are kind of cool, as they are perfectly comfortable laying perpendicular head up or down in a corner of the tank. If I remember correctly burbot do that, too.

Big carp are amazing feeders. The fish we had weighed at least 30 pounds and they could inhale an entire handful of bottom debris along with a couple pieces of corn and exhale all the debris in an instant while keeping the corn back in their mouth. They loved nightcrawlers, but would eat many things, from luncheon meat to boiled potatoes. Like the blue cat, although they looked like brutes, they navigated the tank with graceful elegance.

Longer fish like pike and muskies often didn’t do well in the tank. Once they get themselves headfirst into a corner, they have a hard time backing up, so, often, they end up spooking and going straight up and out of the tank, thus the need for wire screening on the top of the tank when they were being held. It was too stressful for bigger fish, so we tried to shoot them within a day or two. As I say, they often didn’t acclimate well to tank life.

It was somewhat the same with a lake sturgeon of about 50 inches that we kept for a while. The sturgeon was, however, way more laidback and wasn’t prone to spook when it nosed into a corner. The sturgeon ended up in the Great Lakes Aquarium in Duluth. Some of the other fish, including the blue cat, went to the Cabela’s in Grand Forks, North Dakota.

There are so many stories—but just a couple more. The first flathead we had would lay stone-cold flat on the bottom of the tank. You would have thought it was dead, except for occasional gill movement. But I soon noticed that when I would enter the room and move past the tank its beady eyes would often follow me. That one would not feed with the lights on in the room.

We were shooting photos one day and the fish was a bit too far right for the camera, so I reached into the tank with a squeegee on a long stick (used to clean the tank windows) to move the fish over a bit. The fish promptly slid back into its original spot. I moved the fish again. Once again it slide back a couple inches. The third time I touched the fish it went crazy, grabbing the squeegee and shaking it violently for about 3 seconds, before releasing it and again laying there perfectly still. I suppose nothing had ever tried to push this mighty predator around before and the third time was one time too many.

Finally, the longest inhabitant of the tank was a channel catfish I named “Stinks.” The fish entered the tank shortly after it was first filled in 1998, as a tiny fish of about 10 inches. There was by coincidence for many years a small hole under several rocks in one corner of the tank. The fish took up residence there and so far as I know never came out of that hole for at least 10 years. Of course, it must have occasionally come out at night when the room was dark. Once the hole filled in and Stinks grew bigger he slowly habituated to life in the tank, but always at the lowest profile.

Over the years, tank shooting was rendered obsolete, made so by techno advances in underwater filming capabilities with Go- Pros and the legal difficulties involved in keeping fish and transporting them. We always transported and kept fish via permit from the Minnesota Department of Natural Resources. But that generally became unfeasible a decade ago or so. So we haven’t shot in the tank for years, save a few lure shots. These days I use the tank for lure testing.

So, Stinks, a male, became entirely a loner, eventually the sole inhabitant of the tank. I tried introducing female catfish a couple times, but Stinks had become so territorial that he would always turn on them. He probably weighed about 10 pounds toward the end. He liked chicken liver, but then would go off that and want dead suckers for a time, before getting back into chicken liver. Stinks was 24 years old when he died last spring. He rests in peace just outside my office window.

Watching all those fish has been a revelation. Certainly each fish species has their own basic nature, but fish also exhibit individual characteristics at times—in a manner of speaking, they have their own personalities. Pecking orders certainly emerge.

I suppose it’s true that you can never really know someone until you walk a mile in their shoes. That’s the way it is with understanding fish. Nothing beats time on the water targeting them. But watching them also elicits a unique appreciation for the antics of our finned friends.

---