You can always use a $15 lamp dimmer from Lowes to regulate the uth. Any heating device you use will have to be regulated in some way. With uth your only options are a a thermostat or lamp dimmer. If you get a thermostat get a proportional thermostat. They work just like a lamp dimmer. Stay away from zoo med and other companies like them when it comes to thermostats, they make the style known as on/off which means full power then no power which makes a constant temperature fluctuation 84-92. You will never have a constant hot spot temp.