lol, that is too funny, yes a gold bar would be a better "investment" these days!
But you
know what I mean, raising rays could turn out to be like doing the angelfish/discus/African cichlid "breeding thing". I am not saying you would get rich, but I think there is a better than even chance of eventually covering your upfront $ costs for the rays and their upkeep.
I remember a "long time" ago I bred angelfish and sold them to local pet stores for a buck or two each (they were long tailed black veils). I think I figured out that on my labour I made about $4 per hour.
Raising oscars (blood red/tiger cross) worked out better, made about $6 per hour.
So, where would rays come out? If you can breed and sell quality stingrays for somewhere between $1000-2000, and raise a few broods per year, well, it is easy to see how you can actually pay off your upkeep costs of say $200 per month in food and $100 for electricity. After a few broods, you would even pay off your stock and maybe even your equipment. Then from there on out you would be making a profit!
Of course there are risks here, no doubt about that. But compared to some other trophy fish that you can not easily breed and still cost a fortune, at least rays give you a shot at maybe somehow breaking even...
Not to mention, if you can write it all up as a serious business plan and demonstrate its legitimacy, you should be able to write off a lot of expenses on your income taxes...on that last note please obtain professional advice to figure out exactly how to do it!