12 comets from roughly 4'' to roughly 10'' but most around 7'' . feed them twice a day and they consume most if not all food in a minute or two . have never figured out a good way to know if i am over feeding or under feeding . yes , i tried a ''search'' but didn't find it helpful . by the way , we have had a LOT of ''junk'' from trees in the air for probably a month and pond went from clear to real cloudy , looked awful . while deciding what chemical to buy to resolve issue i remembered my '' quilt batting '' and put a layer of it in our savio filter . in about two days pond is again crystal clear . . . . .peace