I have a heat pad under my tank and a 2 heat lamps on the top (one red-on 24/7 and one white-on during the day) and the heat pad is doing nothing. I have sand in my tank (I understand the huge risks but she is 2 years old and I love the look of it). Could I put the heat pad inside the tank buried in the sand? Would that be dangerous? My gecko loves to dig.