Michael....I just had my first batch of pups in June (Motoros). Colin (RVRRays) gave me some advice on care for the pups......it worked great, as one of mine looked bad in the beginning, but now is in great shape. Colin suggested the following:
1. Put the pups in their own system as it is easier to feed them and maintain water quality. Colin said the one time he left his rays in the main tank with the adults, he lost them all. Use a small tank (I put mine in a 36x18 foot print tank that was about 12" tall) (about 30 gallons or so). This size was plenty for the pups and made 50% water changes very simple.
2. Do daily 50% water changes for the pups. I did this for about two weeks, then went to every other day, then to every 3 days. Mine are now about 6 weeks old and were just put in one of my large tanks.
3. Feed the crap out of them. A couple times a day at least. I started with live blackworms. After about 2 weeks they started eating cut up earthworms.
4. Lights- Colin's expirence was that the pups ate mostly at night. I found that to be true also. My pups didn't like light at all for the first few weeks. Whenever a light was on over the tank, they would hide in the shadows. I just started with the light on for an hour or two per day and slowly lengthed the time period. It doesn't seem to bother them now.
As for the batman ray......I've no expirence with them, but have heard they can live as long as normal rays. Some people actually prefer the shape. As long as the rest of the batman ray developed normally, I think he will be fine.
Gestation period is usually 90 to 100 days, but mine was over 120. I've heard it can go as long as 160 days.
Good luck.....If you have any questions, PM me and I'll send you my phone number. Also consider talking to Colin (RVRrays). He has way more breeding expirence than me. I know there are also several other breeding members here too that will likely give you good advice.
Congrats
Pat