My motoro stingray has not eaten in about 4 days. The water parameters are all good and all the other fish in the tank are perfectly healthy. This stingray has been in the tank for months and I have never had a problem. There also appears to be damage to some of the edges to her disc. I am pretty sure she is not getting attacked by any of her tankmates. She is over a foot in diameter. Please help. She used to live eating Massivore Delite but now she won’t except anything I give her. She is in the tank with a black diamond hybrid that is about half her size, a few discus, and a silver aeowana. She is really starting to not look so great. She is not active like she used to be and it is really worrying me.