Wood fired hot tubs are generally different than a gas fired or electric hot tub. With a wood burning hot tub, the spa owners usually fill the hot tub and use it a couple times and drain the water. There is no need for chemicals that is a great advantage for those who want a natural, chemical-free hot tub experience.The wood burning hot tubs by Northern Lights have the option of adding a pump filtering system with four jets. The additional upgrade is available in a 110-120 VAC power source that you can plug into a home outlet which has a GFIC protected plug.Using the same type of wood will allow you get the feel for the right amount of wood and the heating time required reaching the maximum water temperature. Contact us at +1 (800) 759-8990.