I have a 6 inch JD that has been eating gold fish his whole life. He has always been extremely aggressive toward any fish in the tank, even his lady (another super aggressive JD). I recently got 3 red devils, 2 green terrors, and 2 mayans (all between 1.5 and 3 inches), and I threw in about 12 goldfish for them to chase around and kill and eat. To me it is entertaining. The Mayans (both 1.5 inches long) were chasing them around and killing goldfish that were an eighth of an inch longer than they are (super cool to watch) and the rest of the fish would eat them once killed (lazy scavengers). Now there are 8 left and for some reason they aren't being eaten. In fact my big dempsey is protecting them from the other fish. I know he is hungry because he always comes up and "begs" when Im by the tank. The stupid gold fish have been adopted it seems. I want them gone!