We were young, oh so young, and we took on the underwater world without Computers, Backup Regulators, or even Air Gages! We went with unbalanced first stages and breathed the tank until it got hard to breath and then you headed up! It is so funny to listen to debts about bringing back 500psi to the boat! On a single 72cubic foot tank you got 45 to 55 minutes as long as you could suck those last couple breaths! Your dive plan was finish your dive shallow!
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