Abstract: The invention provides a peristaltic metering pump for dosing metered quantitites of fluids along a plurality of flow lines. The pump comprises a set of rollers and a plurality of flexible liquid transfer tubes, the tubes being mounted on a tube mounting against which they are simultaneously compressed by the rollers. The rollers are drivingly connected to a motor, the rollers being mounted on a roller support. The motor is operable to drive the rollers so that they roll successively along the tubes and compress the tubes simultaneously against the tube mounting as they roll along the tubes. The roller support is biassed against a stop with the roller support being movable away from the stop against the bias by force exerted on at least one roller by the tubes.