Hi, welcome aboard.
Have you any experience keeping fish?
Not being rude but if you haven't , saying you are interested in keeping rays is like someone who's never driven saying they are interested in becoming a formula 1 driver. It would be insane to start your fishkeeping hobby with rays.
My first fresh tank was just a beta moved from a glass bowl to a real tank.The second had a different beta i think with pygmy cat fish,sorry i lied I've actually had four freshwater tanks, the next one had an angelfish, five rainbow fish and around four or five pygmy cat fish. Then just an angel with pygmy catfish. The salt had one black clown, a tailspot blend , fire goby ,a neon goby,a peppermint shrimp and a bunch of corals. Right now we have a freshwater tank that has three swordtails, and one or two pygmy catfish.We used to have to angels in this tank and another sword tail but the angels died cause they where fighting and the sword tail had buoyancy issues