11 Installations, apparatus and machines for water purification; water filtering apparatus; Parts of household or industrial installations for water and waste water treatment, namely, plastic media for micro-organisms for water or waste water treatment in bioreactors; household or industrial installations for water or waste water treatment, namely, systems for filtering and purifying water using biological processes; bioreactors for the treatment of water or waste water; all these goods used for checking biofilm growth, reducing risks of clogging of plastic media for micro-organisms and improving efficiency of water or waste water purification throughout the treatment process