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How does moisture enter a tank?
NakedDiver - 1/11/2022 3:46 PM
Category: New Diver Q&A
Replies: 4

Apparently a tank without much air pressure in it can get moisture entering. How is this possible if the tank is air tight? Surly it’s therefore also water tight?
Eric_R - 1/12/2022 7:13 AM
During the fill process is the most likely. Bad air or possible water on the fill whip if they are using a water tank to cool them during fill.
LatitudeAdjustment - 1/12/2022 9:55 AM
Back in the days of J valves we ran tanks low, pulled the lever and began our accent.

I’m guessing we sometimes arrived at the surface with less air pressure in the tank than surface pressure allowing salt water to backflow into the tank. My old 72’s all died from rust :(

You either did the same or your dive shop isn’t keeping up with compressor maintenance :(
DeepSeaExplorer - 7/15/2023 9:22 PM
The yoke connection on the tank can hold back 3,000 psi.

The only way water gets into the tank is at the dive shop.
NakedDiver - 7/16/2023 7:44 AM
I was told leaving a tank in storage with no pressure in it, the damp gets in. Maybe if you left the valve open, or maybe if the valve isn’t 100.00% closed. With pressure, you’re guaranteed any slight amount getting through the valve would be in the outwards direction.