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I'm sure the rays I saw were like yours...the Park Ridge store was the highest priced store I've ever seen--but it supposedly caters to the likes of Michael Jordan, et al. Unfortunately, it's the only place I've ever found FW rays of ANY kind. The rays were in a giant tank with maybe a dozen fair sized Arrowanas swimming about as well.
I have seen the black and white variety, but only at the Shedd Aquarium (great reef exhibit there now for those of you in the Chicago area, BTW)...but that variety gets far too large for a set up my size, though.
I have a 180g that was set up for my blue spot...I've since dismantled and stored it since she died and I'm gearing up for a move. I have been toying with the idea of a FW set up--preferably rays if I can find them. Just picking your brain, since I have zero experience with FW, beyond a betta at my office!
I may do another SW ray tank--yellows maybe, not blue spots, but am investigating other ideas before I decide.