Can I attatch my ZooMed Heat pad directly to tub?

[The Serpent Merchant]

BTW since this is a tub, how does the OP intend to get proper airflow to the pad since most don't have a deep recess on the bottom to allow clearance?

If a UTH is on a good thermostat with the probe directly on the UTH there is no need for air flow over the UTH as any build up in temperature will be detected by the thermostat and power going to the UTH will be reduced maintaining the proper temperature.