My Goldfish range in size of 2-5", about 20 of them. I heard that goldfish do not like loud water...I found this out after the fact, so that would explain why they would hide when the water fall is on, but lately they hide all day long under a rock bridge. My water fall runs from 10am-9pm, they are no where to be seen prior to 10. At night they come out to eat but are very skidish. If you noticed I also posted about a egret visiting my pond for a few days last week, my dog chases it off after awhile, is it posible that the egret has spooked them even though the bird never touched the water??