Potamotrygon motoro is a freshwater stingray that belongs to the potamotrygonidae family. It's distribution is thorough South America and includes Uruguay, Paraná-Paraguay, Orinoco, and Amazon River basins. It gets to about 39 inches and requires a large tank when adult. They thrive in a PH of 5.0 to 6.0 and a DH no greater than 10. Since they are from a tropical climate, they do best in temperatures of 75 - 78° F.
They are make fine aquarium specimens as long as you keep the water parameters right and have enough filtration. Since they get quite large, when selecting a tank for them, give more importance to bottom area than depth, this is where the rays will spend most of their time.
The motoro ray is the most commonly bred species of stingray, it is also the most popular stingray in the ornamental fish trade. This species can reach sexual maturity at a relatively small size, around 12 inches. Because of this is that the motoro is more easily bred in the home aquarium than any other species of stingray that reach maturity at 18 inches or bigger.
An important consideration to keep in mind is that all freshwater stingray species can grow to a large size when full grown. A freshwater stingray aquarium should never be smaller than 50 gallons, since they will soon outgrow smaller aquariums. The rate growth for freshwater stingrays depends on how often and how much they are fed and on water quality. When kept in a well maintained aquarium with optimal food, a freshwater stingray will reach maturity in about 3 years.
