You called me with your thoughts.
There are a lot of Freshwater stingrays. The most commonly sold are from SouthAmerica (mostly from the Potamotrygoron family). Info available on this fish is quite contradictory. For instance, the Motoro stingray is said to grow to 12" in diameter, but some other researchers say that's the size where the ray reaches sexual maturity, and can grow larger. I've heard there are some asian species that stay smaller but are very hard to find for sale.
Currently, I'm keeping 2 Reticulata stingray: some sites say it will grow to a max size of 1' in diameter, while others say it can get to 3 feet wide. I have them in a 250 gallon setup, with a heavyly heavy filtration system.
GROW RATE: I got my first ray in april this year, and was about 4" in diameter. Today, it's almost 7", with a tail of about 8" more. The LFS told me I could keep it in a 20 gallon setup. I did it for 7 days. I bought a 70 gallon tank and kept him there for about 5 months. In July, I bought him a female companion. (grew from 3" to 4.5 inches in 2 months). Since last month, they are living in the 250. I hope I can keep them there for at least 2 years.
FEEDING: They are eating feeder fish, earthworms, tubifex worms. According to my reading, they can be taught to eat shrimp, raw fish, ox heart. I have had no succes. Only living foods.
CAUTION: Stingrays are venoumous and sting! They have a poisonous barb in their tail, which is used maioly for defense. I have not seen them use it for hunting or harrasing other fish. Once, I bothered one with a long stick to see what would happen, and he would just run away from me. However, you could be stung when placing your hands in the water. Their venom is not completely described, so the effects can be from hardly painful to lethal, depending on the species and your personal condition. Be extra careful if you have kisd in your house.
(Also, keeping rays is outlawed in certain states in the US. )
If you have any futher question, post here and I'll try to write a little more. In my signature, I have a link to some pics.
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P.S. I'm not the stingray king.
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