Snakehead spawns in April and June. It is the best time to drop fish, because of the living habits of fish, snakehead will make a nest on algae during this spawning period, and there is no particularly obvious feature on the water surface, but if you carefully distinguish it, you will find that there are broken algae drifting in a smooth round hole on the water surface. The size of fish can be distinguished by the size of the water hole. I hope it helps you.