A skimmer system composed of a base and a slidable float assembly. The base has a base chamber defined by a sidewall, an endwall, and a conduit having an intake communicating with the base chamber. The float assembly has a float chamber defined by an outer float wall, an inner float wall and a top plate. The conduit passes through the inner float wall, wherein a flow channel is disposed therebetween. Preferably the inner float wall carries a flow governor, and the upper end of the inner float wall serves as a weir. An air pocket in the float chamber imparts buoyancy to the float assembly such that the weir skims a top layer of a liquid in which the skimmer system is immersed. A separator may then be used to separate the liquid from material floating on the liquid.