No, direct gas injection under low pressure, the GoreTex/PerTex pore size is small enough to be a barrier for water so when you pass co2 gas into the bladder it can diffuse through these pores and because you can make the bag fit the entire area on the bottom plenum/ugf the corresponding substrate area above the bladder will saturate with co2 as it diffuses/bubbles through. Does that make sense?
🙂