Here's a great paper on ray reproduction. I'm interested in an attempt in breeding at a later stage, but I did find this paper while doing some reading and I thought I would share it. It covers a multitude of reproductive information, including breeding seasons, maturation period, gestation period, season of births in the wild, ovarian and uterine fecundity (potential reproductive capacity), size at reproductive maturity, and a comparison to marine studies. It features several species of rays that are frequently kept in aquaria. It's a published PDF so you can save it for future reading. It's too big too post here.
http://journal.nafo.int/35/charvet-almeida/22-charvet-almeida.pdf
http://journal.nafo.int/35/charvet-almeida/22-charvet-almeida.pdf
