Hyphessobrycon columbianus, a Tetra of a Different Color

Author: Phil Purser

These colorful little tetras are simple to keep, yet stunning–a perfect addition to most community aquariums.

Something Fishy

“Honey,” I said to my wife, “I bought some new fish.” She ran over to the tank in our living room. “Oh, I see them now,” she remarked, fingering the glass. “Wow, those are really pretty; what are they?”

I wasn’t quite sure, but the clerk at the pet shop sold them to me as “red and blue tetras.” Red and blue though they may be, I was entirely unsatisfied and wanted to know more. A little digging around revealed a horrible hodgepodge of broken nomenclature. It seemed no two sources could agree on Latin names and that no two pet dealers in the nation sold these fish under the same common name.

What was the identity of the nickel-sized, red-finned, blue-tinged tetras that I had dropped into my tank? I hit the references to find out all I could about the ins and outs of these fish: their habits, native habitat, diet, breeding, and finally, their Latin name. So here is the scoop on one of the most aesthetically enjoyable and unique little tetras on the market today…

Mysterious Origins

First discovered in the warm, gently flowing waters of a few small streams in the Rio Acandi basin near the Caribbean coast of northern Colombia in the early 1990s, our little mystery fish was initially named the “Colombian tetra.” It had the Latin name Hyphessobrycon ecuadoriensis mistakenly attributed to it, as there isn’t to anyone’s knowledge any population of these fishes in Ecuador. Some hobbyists suggested the taxonomic strategy of scrapping the genus Hyphessobrycon altogether and in its place substituting the genus Astyanax, which includes such large tetra species as the banded tetra and the Mexican cave fish, neither of which have very close relations to the fish in question. Fortunately this solution was not widely accepted. Finally in 2002, Zarske and GÉry stepped up the plate and officially described my little red and blue fish as Hyphessobrycon columbianus.

Of course, a proper Latin name often doesn’t mean anything in the aquarium trade. Usually the names on distributors’ invoices are not the preferred Latin, so pet-shop dealers may order something their customers like once, only to never be able to find it listed under the same name again. They search in vain to reorder the same fish species—talk about frustrating! Around the turn of the millennium, Hyphessobrycon columbianus was coming into the United States and Europe under such names as the blue and red tetra, the red and blue tetra, the blue and red Colombian, the neon-backed tetra, the ghost neon tetra, and even the red-tailed mirror-blue-sided Colombian tetra (whew, what a mouthful!).

Fortunately, around the same time that Zarske and GÉry concluded upon a Latin name, the common-name confusion settled down as well. Now you will probably see these fish being called either the red and blue tetra or the Colombian tetra.

Since 2003, the popularity of Hyphessobrycon columbianus has grown considerably, and large-scale breeding projects have reputedly begun throughout northern Colombia to supply sectors of the market with captive-raised specimens. Hobbyists in the United States have also reported success with captive breeding of these fish, and the selling price has radically dropped. It’s always good to see the stress of collection taken off of wild populations.

Biology & Tank Requirements

Growing to a maximum adult length of just over 2½ inches, H. columbianus is a high-backed species; this fish is definitely more laterally flattened than many of its elongate tetra cousins. The dorsal fin is quite tall, even for a tetra, and sweeps far back on the dorsal surface. The portion of the back anterior to the dorsal fin is oftentimes raised or humped slightly. Some specimens may have a dorsal fin that is yellow to orange in coloration. The head of H. columbianus tapers to a rounded spear-point mouth that is lined with surprisingly large teeth and powerful jaws for such a small fish. The large eyes (proportionally, these eyes are considerably larger than many other tetra species) suggest these fish are active predators whose keen vision is helpful both in spotting prey items and in avoiding would-be predators. With a narrow, muscular caudal peduncle and a tall, sharp-edged caudal fin, H. columbianus is a powerful swimmer built for short bursts of rapid speed. The pectoral fins are also anchored in relatively heavy musculature.

Colors and Stripes

The dorsum and upper portions of the sides are bathed in a gentle wash of slightly iridescent pastel blue that will, under superior water conditions, extend downward to encompass the entire lateral surface. Particularly striking specimens will also sport a bright blue swath of coloration streaking down the midline of the dorsum; I am not exaggerating when I say that this blue stripe may rival the blue on a neon tetra Paracheirodon innesi in intensity. The lower flanks of H. columbianus are bright metallic silver, and they may act as mirrors in certain lighting situations, catching the blue from higher on the dorsum and reflecting; thus this fish may appear entirely blue.

Fins

The belly and caudal fin of this fish comprise the red half of the equation. Beginning at the anterior edge of the anal fin (which is elongate in both sexes of the species), a red coloration fringes the rays, and deepens as it progresses backward. A sort of residual pinkish glow low along the body just above the anal fin (again owing to the mirror-like qualities of the scales along the lateral portions of the body) is also evident in some specimens. The caudal fin, however (and even the caudal peduncle in some specimens), is absolutely awash with fiery bright crimson coloration. As is true with most tropical fish species, these colors may be brighter and more vivid when H. columbianus is exposed to superior water conditions. Conversely, they will display washed-out or faded coloration in poor water conditions or when otherwise stressed. A stressed specimen has a chalky white to ashy colored body with only a hint of red in the tail; no blue is visible.

Living Conditions

The good news, however, is the hardiness of this species. Tough enough to survive relatively wide ranges of pH and temperature, H. columbianus are definitely leading competitors for stocking in the beginner’s aquarium, as they provide both beauty and longevity (as long as five years). They will thrive in pH ranging from 6.5 to 7.5 and will tolerate anything from 71° to 83°F.

Water Requirements

Keep up with your water changes and use plenty of filtration. These fish hail from clean, flowing waters, so keep nitrogenous wastes as low as possible, preferably zero.

Watch for Jumpers

Mid- to upper-level swimmers, these little tetras are highly active during the daylight hours, and perhaps even more so on moonlit nights. In the wild, H. columbianus often feed on aquatic insects and larvae. To catch these foods, the fish sometimes must leap out of the water or make very quick dashes to the top of the water column—acts that may lead to fatal leaps from your tank. Even a covered tank is not absolute security, however, as these little rascals can get quite raucous around feeding time. So take care not to lift a glass lid too high or leave it open when you feed, as it is very easy for a Colombian tetra to jump out of the tank even with you standing right there.

Tank Requirements

These fish do best in heavily planted (real or artificial) tanks and/or those with ample amounts of driftwood or other hiding places. In their native environment, predators are all too common, and any H. columbianus that cannot find quick cover are easy targets. Lack of driftwood and underwater vegetation will severely stress these fish, as too much open water is not in their program for survival in the wild. In fact, a lack of adequate wooden, stone, or vegetative cover may also increase the fish’s propensity for leaping out of the water; even with a lidded tank that prevents escape, a fish may still be injured if it hits a glass lid on a jump.

Feeding

A good captive diet for H. columbianus consists of a mixture of balanced flake foods, brine shrimp, bloodworms, and other tiny foodstuffs. While Colombian tetras may live for years in a captive environment without ever eating anything other than flakes, I highly recommend supplementing their diet with live/frozen feeders such as brine shrimp, as your H. columbianus will never attain their full flush of beauty and color if they eat only flakes. A nutritionally balanced diet truly does bring out the breathtaking best in these fish.

It’s Not Easy

Being Red & Blue

This is one area where I am going to have to step on a few toes of the more respected experts (they shall remain nameless for professionalism’s sake) in the aquarium industry today. It seems that Hyphessobrycon columbianus have attained themselves the reputation (among some circles) of being devious, fin-nipping, and generally riotous members of the tetra family. Some hobbyists tell tales of these demure-looking little fish chasing and harassing larger barbs, tetras, poeciliids, and even some species of large catfish, such as the more peaceable members of the Synodontis genus. Some even report outlandish incidents of an H. columbianus having a fiery enough temper to actually bully the mouth and lips of larger fish in order to force that fish to spit out food it had just eaten. After the harassed fish surrendered its mouthful, the H. columbianus would feed on the spit-out bits!

It has been my experience, however, that the red and blue Colombian tetras are not deserving of such a malicious reputation. While they are active, swift, and curious fish, these tetras have not shown me any of their reputed ill behaviors. But I do recommend that you avoid mixing H. columbianus exclusively with slow-moving, elaborately finned, or easily stressed species.

The rambunctious and fast-paced nature of H. columbianus can certainly be overwhelming to such peaceful species. Mix them with fast-moving tetras such as neons, serpae tetras, rummynoses, zebra danios, hatchets, and Pristella and black skirt tetras. H. columbianus also mix quite well with virtually all species of small barbs, as well as with fish species that dwell at the lowest reaches of the tank, such as the loaches and the catfish of the genus Corydoras. Most specimens of H. columbianus simply will not dive to the lowermost depths of the aquarium, and so don’t typically cross paths with these bottom-dwelling fish, much less harass them.

Despite my not having seen their “bad side,” I will confess that there are some strategies to successfully maintaining H. columbianus in the home aquarium that I do endorse. Bear in mind that these are schooling fish; in the wild, they school together in large numbers to hunt, mate, and avoid predation. So there’s no reason for a hobbyist to expect them to live any differently in the captive environment. When you buy H. columbianus, always buy them in groups of five or six, or even larger numbers. Not only will seeing others of their own kind help to give these tetras a secure, safe feeling, but it will also help curb their instincts to harass your other fish species. Simply stated, if H. columbianus have others of their own kind to play with, they are much happier and much more likely to leave your other fish alone.

Captive Propagation

So far as the matter of captive breeding goes, I think aquarist Paul McFarlane once said it best: “H. columbianus is neither the easiest nor the hardest tetra to spawn.” In fact, a captive pair of H. columbianus can be turned from community pets to spawning stock with minimal effort. If you’re an old hand at propagating egg-laying fish species, you might want to try your luck at breeding the Colombian red and blue tetra. For starters, make certain that you have a pair of H. columbianus.

Sexual dimorphism is not too tricky; males are typically longer than their female counterparts (though females may be equally wide or wider), and they have more vivid coloration under like water conditions. After viewing several specimens in the same tank, it will not be difficult to sex H. columbianus. Then set up a breeding tank that is typical for virtually all tetras. I’ve heard that tanks as small as 5 gallons will work, though I recommend 10- to 15-gallon setups. Use water that is roughly one-third to one-half RO (reverse osmosis) water and one-half to two-thirds conditioned tap water with neutral pH. Once the water conditions are right, introduce the female H. columbianus to the tank first, and give her a couple of days to adjust to the environment. Introduce the male later. If they are both placed in the breeding tank at the same time, the male tends to chase and harangue the female excessively; some breeders report that such harassment can end in the death of the female, though I’ve not personally seen it reach such extremes.

Listed as “egg-scatterers,” female H. columbianus are not very picky when it comes to deposition sites. In the wild, females will deposit their eggs directly into the current of the stream, thus scattering them as far as the flowing waters will carry them. I have heard that H. columbianus will even deposit on bare glass in captivity, though I highly recommend using a laying grid and a couple of breeding mops to catch the eggs and keep them safe, as red-and-blue mommy and daddy may just get the midnight munchies for some of their own offspring. In the wild, this would not be a problem, as the stream’s flow would whisk the eggs safely away from the parents. In the breeding tank, however, proximity can lead to cannibalism.

If your pair of H. columbianus doesn’t appear to be showing interest immediately, don’t lose heart, as these fish tend to be highly secretive in their spawning, and they typically wait for the dark veil of night to shroud their doings. Once eggs have been fertilized, the fry should emerge in roughly four to seven days, depending on the water temperature. Remove the parents to a separate tank immediately, as they will certainly devour the helpless fry (which will instinctively cling to the bottom of the tank for protection’s sake) once they emerge. Raise fry on infusoria, microworms, and liquid fry food. By three weeks, the rapidly growing fry will be large enough to take recently hatched brine shrimp and portions of flakes. Take note that a healthy spawning between one pair of H. columbianus can yield between 80 and 120 fry, so be prepared to responsibly maintain, sell, or give away the offspring of your captive propagation project. Most independently owned pet shops or fish clubs are viable avenues for finding homes for these new fish while picking up a few spare dollars in the process.

Ready for H. columbianus?

In closing, I do not wish to oversell H. columbianus, nor am I going to preach that these fish will change your life or save the world. But what I will say is this: I have been an avid fishkeeper for nearly three decades; I’ve seen, worked with, and bred most of what the freshwater world has to offer, and my display tanks of community tropicals never have less than a dozen or so red and blue Colombian tetras. I’ve had nothing but positive experiences with these delightful little tetras, and I hope that you can too.

See the full article on TFH Digital http://www.tfhdigital.com/tfh/200801/#pg89