You can first try unplugging each of the most common elements dealing with your breaker: the heating element, the ozonator (if you have one), and the blower or air pump. Unplug each individually to find which may be the culprit. First, disconnect all your hot tub components from the GFCI breaker. Reconnect each element to the GFCI breaker and check to see if it trips. If any of them cause your GFCI breaker to trip, it may need replacement. Read the full text about how to fix your tripping GFCI breaker.