[PSUBS-MAILIST] Gamma test dive

[hank pronk via Personal_Submersibles]

Today I dove Gamma to 95 feet in Kimbasket Lake (bush Harbour)  the visibility was awful.
Maybe 2 feet at best.  Big mystery though, when I dive to 95 feet, in a matter of 5 min the pressure inside drops by 500 feet.  The pressure stays right on perfect until I go deeper.  My theory, the water is glacier fed, very cold at depth causing the temp inside the sub to drop, creating negative pressure.  Could that be it?  Vance, did that happen in the north sea?  
On a positive note, I can stop in the water Colum at any depth and hover.  I can surface and stop at ten feet and hover.
Hank