Abstract: The present invention relates to a method and an arrangement in a fibre reclaimer for cleaning of heavy and light contaminate particles from a fibre suspension and said fibre reclaimer comprises at least a vessel (4) having an opening (15) which via a connection arrangement (1, 2) is connectable to a cyclone. The connection arrangement consists of a cone (1) having an outlet (13) with a predetermined diameter (d) and is inserted and located in a conical mantle (2), which with its free end part (14) is fixed to the opening (15) of the vessel (4), whereby the opening (13) is situated a predetermined distance (A) from the opening (15).