How do you know if a ray has internal parasites. I may be paranoid but my little Motoro seems to be acting a little weird. Eats O.K but will only eat earthworms (which i know are fine as my other rays eat them) but she does not seem to be putting any weight on. Today she has started lifting the fron of her disc and the other day i caught her swimming at the top of the water with her eyes above the water line. I have read about this before and remember it was not good news ! I done a water change and she seems O.K but i am not so sure ?