Written by Stacy Griffith
A thermostat tests the temperature then turns the heat pad or light on and off to keep the temperature in a certain range, like the one in your home that controls your heat or air conditioning. Some thermostats come with a probe you can insert into your substrate.
A rheostat or dimmer is a dial that allows the user to adjust the level of heat/light based on their preference but is not automated in anyway. It works like the volume knob in your car. Rheostats can be used with a thermostat but it’s not necessary.