What exactly are they putting in the fish food at the Guangzhou Zoo in Guangzhou, China? We're not used to seeing aquarium fish this aggressive about feeding. Apparently, zoo patrons can pay a small fee for the chance to feed the koi from a baby bottle. And they get quite a show out of the deal too, assuming these fish are as hungry all the time as they were when this footage was taken. We guess it's possible that they were just coming off of an extended fast for Ramadan or something. But slow down, fellas; she's not going to take it away from you. Actually, she will. Better try to hang onto the nipple with your tiny little fish teeth when she pulls that bottle away.