I have the cyklon 5000 and have been looking into the idea of putting some sort of swivel on the second stage, in order to make it more comfortable. I seem to have to keep a pretty hard bite on the mouth piece in order to keep it sealed and not breathing wet. It also seems to help if I keep the end pointed slighty down while diving. I have had it serviced and the LDS did try and find a swivel joint for me. However the poseidon seems to have an odd size hose to modify. Many of the after market mouth pieces don't fit either since the poseidon uses a larger mouth piece. I would like to hear from anyone who may have had this problem also.
DS
DS