One of the JD fish I have dont seem to come out of hiding in these cave ornaments I have in my tank when I have the lights on. One of the two is a bigger one around 4 or 5 inches and he'll stick his head out when food passes by. Then when I turn off the lights for a few seconds he comes out swimming all around the tank and being more active, once again when its time to turn on the lights he retreats back in the cave after a few minutes. The smaller JD doesnt have this problem though, had both of them for weeks now.