Just spitballing, I'm no materials scientist, but the property of water which makes it so well suited to hydraulics is its lack of compressability. If these tub

Just spitballing, I'm no materials scientist, but the property of water which makes it so well suited to hydraulics is its lack of compressability. If these tubes can be crammed full of the stuff then it might increase rigidity to the point where it strengthens the tube's structural characteristics.