If you have a thermostat, then no thats fine. If you dont' have a thermostat the wattage will dictate your temperature, and you'll get a very poor hatch rate, because you'll have very little temp control.
Just spend the $25 on a gqf wafer thermostat vs buying water heater t stats or any other off the shelf junk if you want to get solid hatches. The set points in water heater t stats are for 3-5 degree temp swings. A gqf wafer only allows 1 degree or less.