When I bought my son a zebra, we placed in a tank with lots of rock initially, and he ate well from a stick right from the start. Three months later we moved him to another tank, which had much less rock cover for him to hide in, and he wouldn't eat at all. We moved him back to the tank with more rock, and he ate immediately again. it seems he really liked having the extra cover to hide in. Lately, he comes out everytime I put freezedried plankton in the tank, but he has a hard time tracking it down, as it's light and floats around rather quickly, and his vision, as I understand it, is limited and he relies on smell to find his food.