an improved rotary filter is cylindrical in shape , and operates by vacuum suction or otherwise to withdraw fluids from a substance exposed to the outer area of the device , drawing said fluids into the filter to be pumped out to a suitable reservoir . it includes an inner cylindrical surface having attached thereon a plurality of selectively spaced support structures which extend longitudinally along the inner cylinder . said support structures are covered with a plastic covering adapted to receive a filtering medium which forms the outer circumference of the rotary filter . in one embodiment the plastic covers are grooved to receive a spirally wound wire to further support said filtering medium .