I would like to try MTI hose. Out of curiosity I took a 2 foot section of MTI hose, added an elbow at one end, sealed it with yellow sealant tape, at the open end I wrapped and sealed it with sealant tape, then applied vacuum. The MTI Hose holds at 20 very well. I thought the white covering was supposed to be porous and let the gasses seep  through while blocking the resin? I’m I supposed to take a fine needle and poke holes through the membrane to get it to work? Thanks, Allen