thejennabird was talking about a thermostat, NOT a thermometer. Thermostats control temperature. Thermometers read temperature.
When a UTH isn't hooked up to a thermostat, it's always working at a 100% and will burn your snake if your BP burrows (which BPs are known to do). Either turn off the UTH until you get a thermostat or get a dimmer at your local hardware store for now.
There's two different kind of thermostats: on/off and proportional. On/off thermostats are cheaper because all they do is get the UTH to a set temperature and then turns off. If the temperature falls below set temp, it turns back on again to heat it up again. Proportional thermostats keep the temperature you set. So if you set your proportional temperature at 90F it will keep it at constant 90 degrees.
On the cheaper side you have Hydrofarm thermostats which are on/off type. The proportional brand are VE Electronics and Herpstat (there's more but none come to mind).
Anyways, get a thermostat for your UTH ASAP.
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