Deco Bottles- 30cf vs 40cf?

[NAM001]

Ideally the 30 is more than enough gas for your need however 2 things come to mind.
1. Buddy support. Equip failure or gass loss
2. If you can only get a 2000 psi fill. you will have 20 with the 30 and 27 or so with the 40. Not so ideal

Go for the 40 like some else chimmed. There is probsbly a reason the 40's are out of stock

 

[ucfdiver]

So you think off-gassing only has to do with inert gas going from solution to bubbles in the blood and the rate and volume of respiration of those bubbles is not important? you are right on one thing, you will have more bubbles in your blood, but unless you can respirate them at a fast enough rate with the reduced volume of gas, they are still going to be there when you ascend to the next stop, just a little bit larger. Okay good luck, I'm outa here

ayiyi. That's not how deco algorithms work. If you use a Bühlmann algorithm with gradient factors for example, you're going to have the same amount of bubbles at the beginning of each stop because the algorithm holds you at the previous stop until the point where ascending to your next stop results in you hitting your low, aka limiting gradient factor, which is irrelevant of which deco gas you're on, as a less efficient gas just takes more time.