Bill, 12"+ when they were stocked. I don't feed either. My luck is they might control it after 4 yrs will all that lost fishing but then by that time be huge and not eat it but maybe for one year then stop eating altogether. For now Grass Carp and coontail to me don't mix. Next spring if they don't handle it I will consider them probably a bad investment and probably hit the lake with whitecap. The lost fishing year after year is the main point here. To me they are not a realistic option for a coontail problem if you have to wait that long for good results. The way everyone talks though it doesn't take but 2 yrs. Thats why we tried them to begin with.