i just got a new motoro stingray couple days ago, when i got home i put it inside a small pond (actually it's a part from my pond's filter) with a cold water, and some dirt at the bottom, after 3 days i move it into my new aquarium, with a new water (being treated already with some med.), some plants and also some other fish (barramundi and polypterus) etc.. .,all of sudden my motoro just flipped back and dying, what should i do with it?, any suggestion? 
i'm new in this blog. thanks..

i'm new in this blog. thanks..