594583 A refining apparatus is disclosed to reduce microbial contamination in fluids. The apparatus includes a container (1), at least one LED UV light source (3) and at least one magnetic field generator (5). The light source, magnetic field generator, and container are positioned relative to each other such that when activated the light source and magnetic field generator can act on at least the same part of the inside of the container as each other. The apparatus may be used for treating liquid fuels.
