You really need to have respect for the stingray, this is something that you can't just start doing without a sense of danger. The ray needs to feel comfortable with you, cleaning the tank will help have the stingray get use to you being there. also place the food at the bottom of the aquarium with your hand at a safe distance, so the ray expects your hand to have food in it. then slowly allow the ray to come to you, but do so with caution and never have large movements while in the aquarium and the ray is close to you.
