Scuba Tank Sizes

[rubber chicken]

It's because they can't talk underwater!

[lottie]

Well said! A single 72 has as much air as a closet. If you close the door and just sit there you will have a long time, but if you jump up and down and run in place, it won't last so long. The best thing I can tell you about air consumption is just dive a lot and become comfortable and you will be bringing extra air back!

Hey PapaBear - that's a good analogy...thanks

[Papa Bear]

It's because they can't talk underwater!

That's why we don't let them use the AGA masks!

[Papa Bear]

Hey PapaBear - that's a good analogy...thanks

Your welcome! Dive safe and dive often!

[BamaCaveDiver]

I'm not an expert on this. My wife & I just switched over to Steel Tanks 2 months ago. I wish I had switched sooner. We had alum 80's. Actual capacity on an alum 80 is 77 CUft. On our steel 80's it is 80 CUft.Pressure rating for our Alum 80 was 3000 psi on our steel 80 it is 3550 psi. So I am carrying 20% more air in a much smaller tank. The steel tank is 9 inches shorter than the equiv. Alum tank. I was able to shed 8 pounds of lead from my belt, I now dive with only 4 lbs instead of 12 lbs and I do not go buoyant and the end of my dive. Pamela has shed all her weights. Lets see... mmmm... lighter smaller package that carries 20% more air and lets me shed up to 10 lbs weight. Since you have to wear a tank anyway - It's a no brainer Steel ROCKS!! We do a lot of deep wreck diving, I find myself surfacing with 1500 - 1600 psi after a deep wreck dive, the extra air increases my safety margin, and the higher capacity in the smaller package has made our diving experience much more satisfying.

Not quite...you are only carrying slightly less than an additional 4cuft (3.89610 cuft) in the steel 80 versus the AL 80. The fill pressure is just shy of 20% difference; 3550psi is about 18.333% greater than 3000psi. The higher fill rating on the steel cylinder is what allows you to carry an equal amount of gas in a smaller container.

[BamaCaveDiver]

First I know it is Cubic just like BTW and other abbreviations I use for the qft. Just shorter and easier. Next the "old 72's" were rated at 2250 not 2150! Next I dive with 105s and 120s that ARE 2400psi! So I not sure where you info comes from and I don't care weather it is right or wrong, but don't correct me about tanks, I use quite a number of them in a lot of different circumstances. If you want to state you opinion then fine! But don't speak for me please or change what I said in anyway. I live and dive in the real world all over it and see a lot of combos and know that some places in the world you are lucky to get 2800psi! And some of those places are right here in the states! I have been on many dive boats in California that advertise 3500psi fills. What they don't tell you is you will be waiting a long time for hot fill. My 2400psi 120 is filled to 2800 with ease and that my friend equals almost 20% over and then I have over 140 CUBIC Feet of air. So my point was not to be too technical, but to suggest the differences in tanks and amount of air each will hold. Some people think that a smaller 119 HP 3500psi tank is going to hold as much as my 120 LP 2400psi steel and my point is now way no how! Not in the real world all theory aside! So please don't quote me in the future when opinions are being given! C U later!

Actually PB, a tank is a vessel for containing non-pressurized liquids; a cylinder is the proper vessel for containing gases under pressure (sorry, but after your reply I just couldn't let that one slip by )

There are LP and HP 120's out there (the LP version being a heavy mutha!) These behemouths can't be beat for longer dives when they are pumped up to around 4000psi (if you know of anyone looking to get rid of a couple of those monsters, I would love to add a pair to the collection.)

[hbh2oguard]

Of course I brings SOME air back, not a lot, but it’s pretty hard to run out of bottom time during lobster season when the majority of my dives are pretty shallow looking for bugs. There is just always the question, of how much some will be

[amtrosie]

First I know it is Cubic just like BTW and other abbreviations I use for the qft. Just shorter and easier. Next the "old 72's" were rated at 2250 not 2150! Next I dive with 105s and 120s that ARE 2400psi! So I not sure where you info comes from and I don't care weather it is right or wrong, but don't correct me about tanks, I use quite a number of them in a lot of different circumstances. If you want to state you opinion then fine! But don't speak for me please or change what I said in anyway. I live and dive in the real world all over it and see a lot of combos and know that some places in the world you are lucky to get 2800psi! And some of those places are right here in the states! I have been on many dive boats in California that advertise 3500psi fills. What they don't tell you is you will be waiting a long time for hot fill. My 2400psi 120 is filled to 2800 with ease and that my friend equals almost 20% over and then I have over 140 CUBIC Feet of air. So my point was not to be too technical, but to suggest the differences in tanks and amount of air each will hold. Some people think that a smaller 119 HP 3500psi tank is going to hold as much as my 120 LP 2400psi steel and my point is now way no how! Not in the real world all theory aside! So please don't quote me in the future when opinions are being given! C U later!

My, oh my, oh my, oh my!!!!



Your issues with the dive boats in California, land of the vanishing dream, would obviously be your particular issue. That was not, is not, will not, be the subject of the question and answers. What happens there is not what happens every where else! We, here in Florida, while having difficulty counting ballots, have mastered the art of truth telling with regards to tank filling and advertising. Thank you for pointing out that my memory of 72's was off slightly.

Thank-you, Rubber chicken, for correcting me on the metric equivalents of volume and pressure. Proving in the process the superiority of the metric system. My bad!


One other thing, the minute we set fingers to keyboard, we invite critique of our statements.......food for thought

[acelockco]

Well said! A single 72 has as much air as a closet. If you close the door and just sit there you will have a long time, but if you jump up and down and run in place, it won't last so long. The best thing I can tell you about air consumption is just dive a lot and become comfortable and you will be bringing extra air back!

Are all closets 72 cubic feet?

[Papa Bear]

There are LP and HP 120's out there (the LP version being a heavy mutha!) These behemouths can't be beat for longer dives when they are pumped up to around 4000psi (if you know of anyone looking to get rid of a couple of those monsters, I would love to add a pair to the collection.)

We call it the water heater! The wight I carry in total doesn't change as you know, just the amount on my belt! But with camera in hand I can use all the extra time I can get to get the shot. For Cave I like 105s! Hard to beat and not quite as big as the "Water Heater"!