[PSUBS-MAILIST] gamma external air

[hank pronk via Personal_Submersibles]

Today I am mounting my external 120 cubic foot hp tanks on Gamma.  Is there a reason why I should have a shut off valve on the tank?  It is not like I can get out to shut it off in the water if it is leaking.  I fill the tank from my onboard air compressor, so there is no need to remove the tank.  I have a shut off valve inside the hull at the penetration.  Any thoughts
Hank