The ATF won't bother your rays, this combo should be fine. I do however have two concerns:
First, it is my understanding (and correct me if I'm wrong) that rays don't care for strong current. ATF on the other hand not only enjoy a strong current, they require it to maintain their slime coat and good health.
Second, ATF are notorious for looking and acting just like bait fish when they're small. Babies are infamous for getting eating while small. If you decide to add some, make sure your tigers are big enough to not fit in the ray's mouth.
Finally, I would like to make a suggestion. I think you should consider the dwarf tigerfish, Hydrocynus forskahlii. I notice you have a 225 gallon tank. If you were to go with FATF instead of a Goliath, you could keep your fish for life without having to worry about upgrading in a year or two.