I added a few this spring when the weather was still cool. My pond is only .2 acres and nine feet at the deep end. This was my third attempt to stock them......they all expired in the first two. They were about 7-10 inches. I was amazed to catch three of them so far using a pink rooster tail casting into deeper water. They do fight hard even at that small size and have started sucking up fish food like vacuum cleaners. Not sure why they have flourished this time except that they were stocked when the water temperature was still in the 50 degree range. It will be interesting to see if we still catch them this summer and how they do as the water warms up.