See now I thought about doing that, except I hate running my pax upside down. All that resin then has suction AND gravity pulling it towards the MP when it's upside down. That's why I use the O2 tubing.
look at my vid, I run mine upside down all day, I only use it through the bong when I am at home, so about 2/3rds of the time I am using it upside down. I have no problems with either of my pax, I use them a lot every day. food for thought.
also, an awesome way I have found to use this, I dont put any water in my bong and stack it to the top with ice, as much as as possible, as the bowl cooks the ice melts, right on cue when the oven starts tasting bad the water reaches the perc, creating filtration right at the end of the pack. Pritty cool!