Going through the Cat-eLog, I'm more confused than ever. Wasn't there a Chaetostoma sp.(4)? Maybe I misunderstood. Here is a photo of the fish in question:

I've had this one since July, 2005. If you have a power (or hang-on-back)filter, and the water level is close to the output, this fish is adept enough to climb into the filter. Like this:

If you use a power filter on a tank with this type of fish, please keep the water level about 1/2" below the output.
This species will "run laps" obsessively around the tank glass. I'm not exactly sure why. It may be to eat the Aufwuchs. Or, it may be to claim the territory. Or, they just may need to "run." I had one previous fish like this. He ran laps in a 75 gallon tank for 3 days, counterclockwise. He never switched direction. It seems when they become used to eating zucchini, the lap-running is held to a minimum. I used garlic on a piece of zucchini to lure this species to eat. After that, there hasn't been a problem. The chunk of zucchini seems to be viewed as a "territory" like a rock.
When a male and female(added September, 2005) are together in the tank, they grow fine hairs which take on a bronze hue. More aggression/courtship appeared in the form of tail slapping:


Their diet was 25% protein(mysis, daphnia, brine shrimp), 75% vegetable(zucchini, spinach). There were Distinct territories: (3) large pieces of driftwood and several rocks with algal growth. When one fish would take possession of a territory, the other would want it. They would stay in close proximity of each other for days, into weeks. The closest thing I saw to mating/fighting happened in late December, 2005: The male began tail slapping, quite vigorously. Both were suddenly under the larger piece of driftwood, upside-down, shaking away. First, side-by-side, then face to face. She left the driftwood quickly. He stayed there, fanning his fins. I got a 10 gallon tank ready, for 2 reasons. In case this was fighting, I would need to separate them. If it was mating, I would need a fry tank. Unfortunately, nothing more became of this. He began hogging all of her food, no matter where in the tank I placed it. I moved them to a 20 long tank shortly after this, with a larger filter. I never saw anything close to what happened. Sadly, the female died in late February 2006. I was away for the long weekend and have no idea what happend. He is currently in a 55 gallon tank with Scleromystax barbatus.
Typical aquarium parameters:
pH: 6.4, 80 microSeimens, negligible nitrates/nitrites, temperature: 68-71 degrees F. Water changes at least once weekly, 40%.
Tank set-up: several pieces of driftwood, several 3"-4" rocks(these count as territories), plants are optional, but help keep the water clean. Airstones are preferable to powerheads, since powerheads generate heat. A good current is desirable in the tank, but not a maelstrom. A sunken piece of zucchini in the tank on most days is good for preventing the "manic" lap-running.
These are just a few of my hobbyist observations. Feel free to use them as you wish.

Sincerely,
Amanda