Hysteresis on the GF30 conical fermenter refers to the expected deviation or accepted margin of temperature variation from the target temperature. This deviation allows for a certain amount of temperature fluctuation above and below the target temperature before the necessary heating or cooling is triggered and activated.

To adjust the hysteresis on the GF30 Conical Fermenter Controller, press the 'Set' button, select 'Settings', proceed to 'Hysteresis', and then use the up or down buttons to modify it.