Reversible, suction based adhesion employed by many marine organisms may provide unique, adaptable technologies for biologically inspired grasping devices that function in difficult submerged environments. Here a theoretical framework based on measurable structural, material, and topological properties is developed to better understand a critical aspect of suction based attachment strategies: the leakage rate. The utility of the approach is demonstrated on an experimental apparatus designed to mimic the flow conditions experienced by a suction-based attachment device. Furthermore, the sealing effectiveness of a remora fish on sharkskin is investigated as a biological example.