How big of a tank do I need to house a stingray? What species and possible tank mates?
Motoro are the easiest to feed, one of the biggest issues with keeping many rays. They are also pretty forgiving as far as tank conditions. But with all rays, pristine water is best. If you get a pup, for the short term grow out, a 180 will work. For a permanent home, a 8' by at least 3' wide would be what you are looking at. An 8' x 4' would be better. The height for a stingray tank is not as important as the length and width. There are smaller rays than motoros. But they are harder to keep. Motoros are generally considered good beginner rays. The male motoros stay smaller than the females. But still need a large tank. Tank mates are anything big. Stay away from plecos. But plenty of people keep them together. In the tank size you need to keep them, there are lots of options. Arowana, large SA and CA cichlids including peacockbass. Giant gourami, tin foil barbs, bala sharks. I have seen people keep discus with them. Lots of different characins. If it's big, it will probably work.
Make sure the tank has rounded sides, stingrays don't like corners/sharp objects! -Anthony
Maybe your thinking of jelly fish. Sting rays do fine in rectangle or square tanks.
Thanks for all your help. What is a good size tank in gallons?
450 gallons. 96" x 36" x 30" for a permanent home with tank mates. It can be done in a 6" tank. But I really think that takes more work on your part, and your better off going bigger. Plus bigger allows for more rays, and more fish.