Ona Cyclone Fan The Ona Cyclone Fan is used to distribute Ona odour destroying scents. The fan Unit fits on top of an ONA 20L gel tub, it then distributes the ONA odour destroying vapours around an area of up to 450 square metres, the Cyclone fan is fitted with a fan speed selector switch with 5 running speeds and an OFF position. Simply fit to the top of an Ona 20L tub, plug the power supply into a mains outlet socket and switch on. ONA gel has been destroying odours effectively for many years and is used in hydroponics and commercial applications worldwide. ONA is not only an excellent air freshener, it is a true odour neutralizer – effectively eliminating bad smells. Formulated using a complex formula of essential oils, and contains terpenes. As a result, ONA is very safe to use, is biodegradable and can be applied in almost any situation.