That Fish Blog – Aquarium Advice and Information

Hello, Frank Indiviglio here. Stingrays – mysterious, beautiful and odd – are difficult to resist, and therein lies their main drawback as aquarium fishes. While not particularly delicate, experience with other fishes does not always serve one well where stingrays are concerned. Their husbandry is not well known, and there are a number of special considerations which must be borne in mind.A marine species (the little skate, Leucoraja erinacea) was the first ray to catch my attention. I was about 7 years old, prowling the stalls of NYC’s famous Fulton Fish Market in the pre-dawn light. Accompanied by my grandfather, we were seeking new pets – octopus, turtles, eels and such – that rarely appeared in pet stores at the time. The skates, while living, were in bad shape, but I vowed to give them a try someday. Eventually, freshwater rays appeared in Manhattan aquarium shops, and I was off and running.

Following are some points to consider before purchasing your first freshwater stingray. Having a handle on these matters beforehand will greatly increase your chances of succeeding with these spectacular fishes.

Medical Precautions
Stingrays are venomous animals. While no freshwater species are known to have caused human fatalities, we know very little about the nature of the toxins they produce, and individual sensitivities may be a concern.

Speak with your doctor and arrange for medical care in the event of an emergency before purchasing a stingray.

Selecting an Individual: Size
The small stingrays that appear in the pet trade are not adults but rather are babies of a variety of large species. Even those sold as “teacup rays” will reach at least 18 inches in diameter when mature (2-3 years), and will require a tank measuring 4′ x 2′ x 2′ if they are to thrive. Adults of several trade species approach 3 feet in diameter.

Furnishing the Aquarium
Stingray skin is easily damaged by ornaments that are safe for other fishes; they do best in a sparsely-furnished aquarium. Even small specimens will quickly uproot plants and dislodge filter tubes, aerators and heaters.

Use smooth stones as a substrate. Typical aquarium gravel is too rough and may cause skin lesions. Substrates designed for marine aquariums raise the pH to dangerously high levels and sand, while acceptable, poses water quality problems (please write in for further details).

Stingrays often alight upon aquarium heaters, but seem not to respond to the high temperatures generated. Heaters must always be shielded by a PVC sheath or heavy rocks.

Personal Observations in the Field
While on a field research assignment in Venezuela, I was happily situated within the range of 4 species of freshwater stingrays. The animals spread out onto the flooded grasslands during the rainy season, and were rather easy to find.

The largest individual I observed was dead and floating down the Orinoco River. Spanning nearly 4 feet across, it easily supported the weight of the black vulture that was feeding upon its carcass.

A Hands-On Experience with Stingrays
Please be sure to visit That Fish Place/That Pet Place in Lancaster, PA (the world’s largest pet store) for a chance to hand feed our friendly marine stingrays.

More to follow next week. Until then, please write in with your questions and comments. Thanks, Frank Indiviglio.

Further Reading
Please check out the book Freshwater Stingrays.

An interesting article on the conservation of South American stingrays is posted at http://www.cites.org/common/com/ac/20/E20-inf-08.pdf.

Image referenced from Wikipedia and originally published by Raimond Spekking.