The Dolphin Clinic Essential Oil Electric Vaporiser is designed to be used with Pure Therapeutic Grade Essential Oils only. The type of oils used will affect the vaporiser performance, the aroma and the therapeutic benefits. We recommend you only use Dolphin Clinic Pure essential Oils and Pure Essential Oil Blends. You can leave the vaporsier on all the time, just add more essential oils when you want to increase the aroma again. These are very economical to run costing no more than a standard light bulb. The new Dolphin Clinic Vaporisers come in a funky new design.