Top of the Food Chain: Taming the Untamable-- Giant Payara!


Author: Brian M. Scott

My first experiences with payara were some 20 years ago now (I can’t believe I am even old enough to say that!). Anyway, I can remember cruising through the aisles of my favorite pet shops, and once in a while I would come across these big flashy silver fish with absolutely gargantuan teeth. I remember thinking they were such ugly and nasty critters, almost freakish-looking water wolves. Who on earth would want such a thing in their tank? Granted, at the time I was into barbs and smaller “community” species, and big predatory fishes were simply not an option for my 20-gallon aquarium. Fast-forward to 2006 and my, how things have changed!

Tough to Find

As with many fishes, the payara was a very difficult fish to obtain and maintain in aquaria until very recently. Years ago their worst enemies in aquariums were aggressive bacterial infections that came about from poor handling and quarantine techniques, common on both ends of their travels, from the collectors to the importers. In fact, I would bet that few ever really lived more than a few months in captivity after import. Almost all of them that I saw had badly swollen snouts and very ragged fins, which were usually red and inflamed from severe ammonia burn during transport.

Thankfully, today we have far better collection, holding, and transport techniques than even just a few short years ago. Therefore we are now able to obtain specimens of rare and unique fishes, such as payara, that are healthy (for the most part) and in good condition. Of course they still often need a touch of TLC during the various steps of transport.

The Biggest Payara

The group collectively known as payara contains several species, but I will only be covering the venerable Hydrolycus armatus in this article. The largest of the clan, H. armatus is capable of growing to more than 3 feet in total length, thus making it a very highly sought-after food and game fish in its native waters of northern South America—specifically the Rio Orinoco drainage and the vast, winding rivers of the Guyanas.

H. armatus is a powerful, sleek, and fast-moving species that is adept at living in several habitats across its native range. Paul Reiss, a well-known professional fisherman and the owner and operator of Acute Angling, reports that payara are most commonly found in extremely fast-flowing water. In aquariums, we have found that they do not necessarily need such strong current in order to thrive, but they do prefer water that has some degree of turbulence to it.

Feeding the Beasts

Just a quick glance at their teeth should tell you that payara are obviously carnivorous by nature, and specifically they are considered piscivorous—that is, they eat fishes. In aquariums, and as with all types of predatory fishes, it is best to attempt to convert these predators to a diet of non-living foods. Today we are blessed with a variety of various types of fresh and frozen foods like never before. I cannot stress enough the importance of converting payara to a diet of fresh smelt, mackerel, or other type of non-living food fish.

There are also many types of frozen fishes that are very suitable for inclusion in the diet of tanked payara. Since payara are more often sold as juveniles, common silversides work extremely well as a staple food fish due to their smaller size. Of course, as the payara grow, their food will have to increase in size and quantity, too.

After you have converted your payara to feed on non-living whole fishes, the next step is to get them to consume a variety of other forms of seafood. I have used chopped squid, clam, and fish flesh with good success over the years. But I should also mention here that I primarily have kept the sister species H. scomberoides, which is a smaller, more aquarium-tolerant species of payara that should not be confused with the mighty H. armatus. Regardless, the care of H. scomberoides is nearly identical to that of its bigger cousin—only with H. armatus everything must be much, much larger!

Tanking the Beasts

It is probably pretty apparent that these fish need huge tanks. It’s difficult for me to convey to you just how large these fish grow. Even though hobbyists keeping H. armatus report that they do not swim nearly as much as one might initially think, I still very strongly recommend that the absolute largest tank possible be used for their keeping.

While H. armatus are not considered jumpers in the sense that they readily leap from the water, like arowana for example, they do have highly developed pectoral fins that enable them to rapidly rise to the surface—usually while in pursuit of prey. This rapid ascent will often lead to a quick break through the water’s surface. Since H. armatus have a pronounced nuchal region, they can easily become damaged if allowed to hit the aquarium’s canopy or cover glass. Repeated strikes to this region have caused unsightly scarring to the outer tissue, which can, and often does, lead to severe bacterial infections. Of course, any bacterial infection is serious and should be considered life threatening.

Tank Parameters

The ideal tank for payara is one that has minimal decorations, as these fish will often strike them while in pursuit of prey—especially if offered live fishes as feeders. The tank should have the sides and back painted black, or at least dark in color. This will bring out the fish’s best colors. Payara tend to inhabit deeper waters, so they are not accustomed to overly bright light, which may stress them in the ultra-clear water of an aquarium. Speaking of lighting, the tank’s illumination should be minimal and only afford the hobbyist to see sections of the tank clearly, which is generally referred to as “spotlighting.” Several very large enclosures that I have seen have utilized this illumination technique; it is really effective, visually speaking, and the fish seem to do very well with it.

Tankmates

Tankmates are probably a no-no on a long-term basis. Sure, while H. armatus is young it will be fine, as long as the tankmates cannot be swallowed and are not overly aggressive to the point that the payara stress out from their presence. I tend to err on the side of caution, however, and fear that tankmates will cause more harm than good with these fish—especially at the going rate for H. armatus these days! Don’t get me wrong, plenty of people keep payara with other fishes and have zero problems, I just prefer to maintain them in a single-species, single-specimen type of aquarium setup.

If you do want to try and keep tankmates with payara, there are a few species that I have seen work. First are some of the larger barbs, like spanner or tinfoil barbs. Silver dollars seem to work well, too. Some folks have kept large peacock bass in with their payara, but I fear that the peacock bass are too aggressive when it comes to feeding time, thus I would hesitate to house them together. The same is true for other large cichlids, like wolf cichlids or oscars.

Large catfishes should be excluded from a setup containing payara, as their nighttime forays will inadvertently freak out the payara and perhaps cause them to damage themselves by slamming into the tank’s glass, canopy, and decorations, as well as into other fishes. That having been said, though, I did see one nice display of H. armatus that contained several large pleco-type sucker-mouth catfish. Needless to say, the tank was spotless!

One of the most striking displays that I have ever seen was a very large aquarium in Germany, probably somewhere in the range of 2000 or 3000 gallons. The tank contained a single H. armatus and several huge, fully mature river stingrays. It had a deep sandbed and dim lighting. The payara was like a ghost swimming in and out of the shadows. I remember being surprised to see how little current there was in the tank, but the fish were all very healthy and flawless in condition.

Water Quality Concerns

Payara generally do very poorly in aquariums that have bad water quality. On the whole, payara are very sensitive to water containing a high level of dissolved metabolites. I have found, through trial and error, that the best way to maintain proper water quality is to perform very large and very frequent water changes. Never change a large percentage of water and clean the filter at the same time, however, as doing so will surely destroy too much of the beneficial bacteria colony, resulting in the aquarium becoming unbalanced. An unbalanced aquarium will have rising and falling levels of toxic compounds, such as ammonia, ammonium, and nitrites. Payara that are exposed to these compounds will often break out in lesions, which quickly become infected and may lead to death.

The pH, hardness, and alkalinity of an aquarium containing payara are not nearly as critical, so long as extremes are avoided. A general pH of 7 (neutral) is good. Hardness and alkalinity measuring in the “moderate” range is perfectly acceptable as well.

Really Big Fish

Payara are characins belonging to the subfamily Cynodontinae, the root of which literally translates from Latin into “dogtooth” in English. They are capable of exceeding 3 feet in total length and nearly 40 pounds in overall weight—now that’s a big, toothy tetra!

My, What Big Teeth You Have!

The enlarged canine teeth exhibited by payara enable them to trap their prey, thus allowing them to hold onto the fish until they can be positioned safely for ingestion, which occurs whole and head-first. Only rarely are the eaten fishes actually punctured by the huge canines, but rather are held behind them before being swallowed. In aquariums, payara are more likely to just swallow the fish whole without employing this holding action; perhaps in absence of a strong current, the need to hold their prey firmly is greatly reduced.

Final Thoughts

Payara are true giants in the fish world. Known more as game fish than aquarium fish in their native waters, these fascinating creatures are a sight to behold in a large display aquarium. They grow to immense proportions and consume only meaty foods, but their care is easy so long as the basics are afforded to them. While volumes can be written about this interesting and exciting group of fishes, it simply cannot be done here. I invite you to visit one of the fine Internet discussion forums advertised in this column for more information on these fishes and to speak to other hobbyists who are just as interested in learning all there is to know about the venerable payara.

Acknowledgements

I would like to thank Paul Reiss of Acute Angling for providing top-shelf information from first-hand knowledge of payara in their native waters, and I would like to extend a special thanks to the fine members of waterwolves.com for their continued support and helpful knowledge about the predators covered in my column.

Tip Box:
Really Big Fish

Payara are characins belonging to the subfamily Cynodontinae, the root of which literally translates from Latin into “dogtooth” in English. They are capable of exceeding 3 feet in total length and nearly 40 pounds in overall weight—now that’s a big, toothy tetra!

Tip Box 2:
Teeth You Have!

The enlarged canine teeth exhibited by payara enable them to trap their prey, thus allowing them to hold onto the fish until they can be positioned safely for ingestion, which occurs whole and head-first. Only rarely are the eaten fishes actually punctured by the huge canines, but rather are held behind them before being swallowed. In aquariums, payara are more likely to just swallow the fish whole without employing this holding action; perhaps in absence of a strong current, the need to hold their prey firmly is greatly reduced.

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