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cshel
09-30-2007, 16:02
Hail ye experienced scuba gurus:

My SO got certified a few weeks ago. He and I have been diving non stop ever since. Ok, every chance we've had. He now has 12 dives in 3 weeks! The problem we have is that he uses his air much faster than I do. I have an AL 80 and I surface with 1000-1200 lb of air left while he is at 500-700 lbs. which calls our dive.

Doing the math, we figure if he takes 20% more down with him... we might end up closer to even. Not to mention more bottom time. We can't seem to locate a shop that rents regular air in 100's or 120's.

Do you think this will help? Should we go ahead and take the Nitrox course?
Should we just buy him a steel 120 and be done with it?


You input is requested.

Thanks,
Cshel

Kidder
09-30-2007, 16:06
I would suggest that your buddy needs more practice. Here's a link with some good suggestions. He probably needs better buoyancy control and steady his breathing in general.
http://forum.scubatoys.com/showthread.php?t=3918&highlight=air+consumption

Also try this one
http://forum.scubatoys.com/showthread.php?t=4149&highlight=air+consumption

Capt Hook
09-30-2007, 16:07
When we started out, my wife used an AL63 and I used an AL80. After 30 or so dives i got better air consumption and we evened out. Now we both use about the same amount of air on a dive.

finflippers
09-30-2007, 16:10
Hail ye experienced scuba gurus:

My SO got certified a few weeks ago. He and I have been diving non stop ever since. Ok, every chance we've had. He now has 12 dives in 3 weeks! The problem we have is that he uses his air much faster than I do. I have an AL 80 and I surface with 1000-1200 lb of air left while he is at 500-700 lbs. which calls our dive.

Doing the math, we figure if he takes 20% more down with him... we might end up closer to even. Not to mention more bottom time. We can't seem to locate a shop that rents regular air in 100's or 120's.

Do you think this will help? Should we go ahead and take the Nitrox course?
Should we just buy him a steel 120 and be done with it?


You input is requested.

Thanks,
Cshel

Nitrox will not help with air usage.

Next time you are diving watch his position in the water if he is not horizontal then he might need to move some weight around to help trim him out. Not being properly trimmed will cause drag which inturn will make him work harder and use more air.

Also make sure he is properly weighted. Too much weight will cause him to use more air.

As he dives more he will also use less air.

cshel
09-30-2007, 17:13
He's been reading and so have I, thank you.

His trim is good, stays horizontal. He's not overweighted either. We practice every dive with bouyency when he gets low, just before we come out. We are going down again next weekend. He has improved greatly in a short period of time. Doesn't use his arms, stays level, stays close by his buddy.... :smiley2: He'll concentrate on slower breaths. Thanks again.

thesmoothdome
09-30-2007, 17:21
Air consumption improves the more you dive. Of course, a bigger tank will make up for any disparities between diving too, so if money's not an issue a steel 100 would help until he builds the bottom time through relaxation.

Theepdinker
09-30-2007, 18:19
You didn't give a few particulars about your SO.
Everybody seems to have assumed beginner problems.

My situation is similar to yours air wise.
My DB uses an AL80 & I dive a HP 100.
Our dives end according to our dive plan.
We typically have equal percentages remaining in our tanks.
I have MUCH more experience than my DB.
Why do I use 20% more air than my DB?
I'm 6'1" male, my DB is 5'4" female.

Sometimes a person need more air than another.
Get your SO a larger tank & dive.


Theep

Kidder
09-30-2007, 18:30
You didn't give a few particulars about your SO.
Everybody seems to have assumed beginner problems.

My situation is similar to yours air wise.
My DB uses an AL80 & I dive a HP 100.
Our dives end according to our dive plan.
We typically have equal percentages remaining in our tanks.
I have MUCH more experience than my DB.
Why do I use 20% more air than my DB?
I'm 6'1" male, my DB is 5'4" female.

Sometimes a person need more air than another.
Get your SO a larger tank & dive.


Theep

My wife uses much less air than everyone. I heard that females have signifigantly less lung capacity and therefore use less air.

cshel
09-30-2007, 18:36
OK, my SO/DB is 6 ft male, I'm 5'6" and he does outweigh me. But we both could stand to lose 20-30 lbs.

I'm also a singer, maybe I know how to control my breathing better.

FishFood
09-30-2007, 18:56
Unless he leaves you to go back up, hopefully yalls bottom times ARE equall :)


Really though, just give him a few dives. Itll settle down to a mroe reasonable level.

cshel
09-30-2007, 19:01
Of course. We are good buddies. Like I said, his air calls the dive every time.

cshel
10-08-2007, 20:48
Boris and I have been diving every chance we get. We went out today and we had our longest dive EVER!!! We were down for 63 minutes!!!! Boris still had about 500 psi and I had 700 psi! We have been steadily dropping weight and working on our breathing. I've dropped 6 lbs over the last 5 dives. :smiley20:

Daved
10-08-2007, 21:18
I am the original air pig! In my OW dives I had to buddy breath off my instructor.
The more he dives--the better he will utilize his air.

Boris42
10-08-2007, 22:17
Boris and I have been diving every chance we get. We went out today and we had our longest dive EVER!!! We were down for 63 minutes!!!! Boris still had about 500 psi and I had 700 psi! We have been steadily dropping weight and working on our breathing. I've dropped 6 lbs over the last 5 dives. :smiley20:

I just finished calculating our SACs. Mine was .62 and Cshels was .57! Not a bad improvement from the .99 just a few dives ago for me!!

Aussie
10-09-2007, 06:29
Quickest suggestion would be to get Boris a bigger cylinder (100cf+). Like everyone said more dives you both do and the more comfortable, streamlined and less weight you carry will improve your air consumption.
Enjoy yourselves while your diving foremost and dont worry about too much about the differences in air consumption.

Aussie

No Misses
10-09-2007, 13:58
One more point. If one diver is lower in the water column he/she will use more air than his/her buddy. An example of this is when people are lobster hunting. some divers like to have thier noses in the sand and look under every ledge. Other divers stay high and survey the area for most likely places for bugs. The high diver will always use less air. The "nose in sand" diver is deeper and tends to dart around more, thus using more air. JM2c

mitsuguy
10-12-2007, 23:22
when it comes down to it, I think at least some portion of it has to do with body and lung size... I have similar air consumption rates as my instructor, but my wife uses 1/3 less air every time... to the point we started getting her the 63 cf cylinders... which works out well, she's 110 lbs and 5'2", I'm 190 and 6', so she can stand to carry less out of water weight when needed as well...

moral of the story - if you are a good breather, it may not matter how well he does if you have different lung capacities and body sizes...

tbuckalew
10-13-2007, 12:00
Yes, if he dove a higher volume tank, that would help "even out" your dive times. But his air consumption and yours may never be the same on the same volume tank. There are sooooo many variables ranging from each other's overall body mass, metabolism, fitness level, diving techniques, etc.

Simply put, it if really is important and you guys want to add that extra time, he will need a larger tank. Otherwise, he will have to look at ways to improve his consumption by improving his fitness level and improving diving technique (the more you dive, the better you get)!

datamunk
10-13-2007, 12:31
good job boris on bettering your air consumption. i remember being told that your exhale should be twice as long as your inhale. just long slow breaths ;) few more dives and your air consump will be great. already a vast improvement, congrats!

what was the depth of that 63min dive? i cant imagine very deep?

but, like everyone has said, if ya want to buy a pretty steel 100... i love using them, i am an air hog. lets me last a good long while tho.

cshel
10-13-2007, 15:15
what was the depth of that 63min dive? i cant imagine very deep?

OK, we were in the quarry and only 35 max that dive... but we were working on bouyency and breathing. It was really cool being able to add an entire hour to our Bottom Time to date entries. :smiley2: