I have a 90 gallon tank with three bumble bee platties. I originally had two but a fry popped up soon after. Couple months later all are fine. One if my original platties does like to hide sometimes for a few days. Now my newest (fry) is almost as big as the others. Thing is I haven't seen it for three days now. I have large ocean rocks and live plants. I even lifted the rocks which have many crater holes but no sign if him/her. The tank is covered. Could it be hiding inside one if the rocks? Thanks