I read that giving goldfish a bit of orange is good for them but now my fish are

[J Y]

acting differently, help!? Go ahead and make fun of me, please get that out of the way! I was tired of my fish always being at the top of the tank after feeding them like they were hungry so I looked for alternatives. I read about brine shrimp, peas and oranges. I put a small slice of orange in the water. Now they are acting completely different. They are at the bottom of the tank, very skiddish and hiding. Any advice? We changed the water and there is no change in their behavior. What a bummer, please help!