Motoro Stingray (Potamotrygon motoro) 7"

The Motoro Stingray (Potamotrygon motoro), also called the Ocellate River Stingray, is the most popular freshwater stingray in the aquarium hobby. Native to South American river basins like the Amazon and Orinoco, these fascinating bottom-dwellers are famous for their circular bodies and striking orange-yellow spots. Because they require massive tanks, immaculate water, and careful handling due to a venomous tail spine, they are recommended only for advanced aquarists.

Species Overview & Quick Stats

Scientific Name: Potamotrygon motoro

Common Names: Motoro Stingray, Ocellate River Stingray, Peacock-Eye Stingray

Wild Origin: South America (Amazon, Orinoco, and Paraná-Paraguay basins)

Adult Size: 50 to 60 cm (20 to 24 inches) in disc width, excluding the tail

Lifespan: 10 to 15+ years with proper husbandryTemperament: Peaceful but predatory toward small fish.

Aquarium Care & Tank Requirements

Keeping a Motoro Stingray is a major commitment. They grow rapidly and require high-end filtration equipment.

Tank Size: You need a minimum of 180 to 264 gallons (approx. 700 to 1,000 liters) for a single adult. Tank footprint (length and width) is far more important than height so they have room to turn around.

Water Parameters:Temperature: 24°C–28°C (75°F–82°F)

pH Range: 6.0–7.5 (They prefer slightly soft, acidic conditions)

Ammonia/Nitrite: Strictly 0 ppm. Rays produce massive amounts of waste and are highly sensitive to poor water quality.

Filtration: Heavy-duty mechanical and biological filtration (such as a large sump system) is highly recommended. Expect to do 20% to 50% weekly water changes.

Substrate & Decor: Use fine, soft sand or a bare-bottom setup. Coarse gravel will scratch their delicate undersides and cause deadly bacterial infections. Keep decorations to a minimum to maximize open floor space.

Diet & Nutrition

Motoro Stingrays are strict carnivores with fast metabolisms. They use their sense of smell and electroreceptive snouts to find food hidden in the sand.

Juveniles: Feed small live or frozen foods like bloodworms, mysis shrimp, and brine shrimp.

Adults: Feed larger meaty items like earthworms, krill, fresh shrimp, mussels, clams, and pieces of white fish fillet.

Note: Avoid feeding cheap live "feeder fish" (like goldfish), as they lack nutrition and frequently carry diseases.

Tank Mates & Safety

Compatibility: They should only live with large, peaceful fish that stay in the middle or upper layers of the tank. Excellent choices include large tinfoil barbs, Severums, Geophagus, and large Oscars.

Who to Avoid: Do not keep them with small fish (which will be eaten) or aggressive bottom-dwellers (like large plecos, which may suck on the ray's protective slime coat).

Venom Warning: The Motoro Stingray has one or more venomous spines on its tail for self-defense. While they are not aggressive, a sting is intensely painful to humans. Use extreme caution during tank maintenance, and never catch them with standard mesh nets.