Abstract: A multi-phase separating apparatus for fluid containing a gaseous component. The apparatus includes a first tank which receives a stream of the multi-phase fluid which is to be resolved into discrete components. A second or separating tank positioned at a lower elevation than the first tank, receives a stream of substantially gas-free liquid. Said gas-free multi-liquid stream is conducted through a valved conduit. The latter includes a buoyant element which is displaceable by liquid in the lower tank, to form a barrier to avoid backflow or oscillatory fluid response of said liquid. Liquid accumulated in the lower tank thus maintains said tank in a substantially full condition. Liquid monitors in the separating tank monitor liquid levels and control outflow from the unit.