Need Help With Disc Curl

i came into having a teacup ray about 6 inch disc. i had no where else to put him but in with a tank that has a 8-9 inch rtc and some earth eaters and a arowana. i introduced the ray into the tank,all was well,came back 5 min later to see the rtc trying to eat him! yanked the cat out of the tank and he spit out the ray, the ray is alive and swimming but the edges of his disc are curled up, is there anything i can do for him? should i go get a tank to qt and treat him and how
thanks
i really dnt want to hear any non useful comments

thanks, should i put it in a tank alone?

nvm he past on to ray heaven tonight stupid rtc