Biological filter for indoor use

摘要

The biological filter comprises a tank containing water and plants whose roots are embedded in a bulk bed of thimble-sized bodies upon the surface of which reside colonies of suitable microorganisms. The microorganisms feed on dissolved nutrients introduced into the water by air which is sucked by pump from the surrounding air space. The biological air filter is mobile or movable and may be fixed to a wall, be suspended from the ceiling or overhead beam, hang from a suitable door or suitable large window. The tank has protection from unwanted spillage caused by movement.