A reduced pressure treatment system includes a porous pad positioned at a tissue site and a canister having a collection chamber, an inlet, and an outlet. The inlet is fluidly connected to the porous pad. A reduced pressure source is fluidly connected to the outlet of the canister to such that fluid from the tissue site may be drawn into the collection chamber. A hydrophobic filter is positioned adjacent the outlet to prevent liquid from exiting the collection chamber through the outlet. A baffle is positioned within the canister to create a tortuous path between the inlet and the outlet to prevent premature blocking of the hydrophobic filter.