Yea I tried using water, even with the hose at full pressure to the point where I could hardly hold the cork plug
I made for the outlet, neither end cap budged a bit. I ended up using a vice and two sets of very large channel locks with two people pulling against each other while twisting off the end cap. Not typical tools most small cruising boats have so I was lucky to have a super yacht with a kind engineer
to help me in their shop space.
In the end, we got the caps off, but they now look like they have been chewed up by a pit bull. I got the new membrane in, and it all works, but I still cannot believe that Dessalator would design something so stupid. I would never buy this system for my boat
as long as it is this difficult to replace a membrane. A system should be serviceable, or it is poorly designed.