Huge air consumption even after +200 dives

[Blackcrusader]

Hey @Tycksel - fellow dive master here. My sac is always higher when I'm working a class or even leading a dive for friends.

I just finished a trip to the Philippines where I was lucky enough to get paired with an ex underwater demolitions specialist. He was a big, fit guy who went through a lot of air. I don't know how many dives he has, but I guarantee you it was more than my 900. That guy was way more of a bad ass diver than I'll ever be. He was trim, quiet in the water, calm, unassuming, observant, etc. He dived a 100CF tank to our 80's and would sometimes be the one calling the dive even though the rest of us were diving with cameras.

Just keep diving!

Yup just keep diving. Broke my camera tray so not taking any photos or video.
Switched to nitrox 32% and just dawdled around. My first dive this morning.
Dropped my gas down to .6 bar/min from .73 the other day.

Choppy ride to the site but calm waters below. Second dive ave 18m depth Not doing afternoon dives but came back to my room to watch Kill Bill 1. A nice movie to watch after some dives lol

 

[Centrals]

@Tycksel
You are a big guy so air consumption is logically bigger than I. Mine is about three times less than you. You probably has to accept the fact.
When I was diving in Koh Tao in Thailand, the dm in one particular shop carried a redundancy tank on every deep dive with no exception. So perhaps an extra 6L tank would help.

 

[Centrals]

Yup just keep diving. Broke my camera tray so not taking any photos or video.
Switched to nitrox 32% and just dawdled around. My first dive this morning.
Dropped my gas down to .6 bar/min from .73 the other day.

Choppy ride to the site but calm waters below. Second dive ave 18m depth Not doing afternoon dives but came back to my room to watch Kill Bill 1. A nice movie to watch after some dives lol

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If you cannot contribute any positive reply then you might as well not bother at all.

 

[Tycksel]

Little updates. In this chart I have done 200 dives in this trip (400 dives total).

Average SAC: 16,84
Max SAC: 23,9
Min SAC: 13,4

What I've noticed, that breathing techniques or am I leading vs fundiving doesn't affect my SAC rate. Doesn't matter if it's 3sec in, 3sec out or 7sec in, 10 sec out. What actually affects is mental things. When I'm really calm and on "zen" state underwater, then my SAC rate is 13-14L/min which is good for my size I guess.

I just don't understand why most dives I feel super comfortable and next day I can opposite feel super uncomfortable underwater, even when divesites and conditions are similar. Like in my last dive I almost panicked and wanted to end dive in first 5 minutes, and I was fundiving with familiar divesite and perfect conditions.

 

[Blackcrusader]

What actually affects is mental things.

Seems to be this more than diving conditions. If you sac rate is 13 and the same dive with same conditions the next day you are at 20 then that would mean perhaps you are thinking too much.

My best dives are where I don't have to think about anything. I am just drifting alone or doing very slow fin kicks in still water where I an stop at one place and just look at the tiny critters for a few mintues. Hermit crabs I can watch for several minutes.

You can hear my breathing in this video. I try to dive like this lion fish. Subtle movements but always going slow.

 

[Blackcrusader]

I just don't understand why most dives I feel super comfortable and next day I can opposite feel super uncomfortable underwater, even when divesites and conditions are similar. Like in my last dive I almost panicked and wanted to end dive in first 5 minutes, and I was fundiving with familiar divesite and perfect conditions.

Yes some other issue then? This is a DM I dived with in Cebu. He's good on air but he was surprised I am better on gas consumption than he his. He really relaxes diving with me as he doesn't think about me on the dive. He can fun dive with me. Any reason you almost panicked? you need to determine why you would have such anxiety on a dive in perfect confitions on a site you are familiar with.

For me when I am really relaxed my favourite songs and music pop into my head. Other divers have said they can here me humming on my dives when they are really close to me lol I used to play a 4 valve Euphomium and Trombones. You learn as a musician how to extend and control your breathing.

 

[grantmac]

I think you've got an anxiety disorder.

 

[GS-111]

I'm a 193cm/120kg 40y guy and working as a divemaster...SAC rate is around 21-24l/min...
I'm almost always first who runs out of air...I use 12L alu tank and we don't have bigger tanks in our dive center. Also diving with sidemount is not allowed when leading customers...

Relaxation is, as others say and I'm sure you know, generally the key and I’m sorry that my message may not help that.

I re-read you OP. You are a divemaster paid to lead customer and concerned about your SAC because you say you are “…almost always first who runs out of air”.

Your reported SAC rate is a bit higher than average, but you say you are “193cm/120kg 40y guy” and, particularly if there is any stress in check on your group, pretty much explains the largest element of that. And you know that.

You also know if you were diving for pleasure this is not really an issue. As others point out you might choose to use a larger (15l) single tank when available, go on doubles or have slightly shorter dive plans than some others.

However, as a professional (paid) guide it’s a bit different. How much is this affecting your job? You know full well that at the end of your most demanding guided dive route you need enough gas for a controlled ascent and safety stop while buddy breathing with a stranger.

You don’t say but if there is any question of either putting yourself at risk of OOA or curtailing the advertised experience for your customers you need to tell your employer. And, yes, recognise that if they are unsympathetic the outcome may not be what you want.

I hope it works out.

 

[Tycksel]

Relaxation is, as others say and I'm sure you know, generally the key and I’m sorry that my message may not help that.

I re-read you OP. You are a divemaster paid to lead customer and concerned about your SAC because you say you are “…almost always first who runs out of air”.

Your reported SAC rate is a bit higher than average, but you say you are “193cm/120kg 40y guy” and, particularly if there is any stress in check on your group, pretty much explains the largest element of that. And you know that.

You also know if you were diving for pleasure this is not really an issue. As others point out you might choose to use a larger (15l) single tank when available, go on doubles or have slightly shorter dive plans than some others.

However, as a professional (paid) guide it’s a bit different. How much is this affecting your job? You know full well that at the end of your most demanding guided dive route you need enough gas for a controlled ascent and safety stop while buddy breathing with a stranger.

You don’t say but if there is any question of either putting yourself at risk of OOA or curtailing the advertised experience for your customers you need to tell your employer. And, yes, recognise that if they are unsympathetic the outcome may not be what you want.

I hope it works out.

It's not problem anymore, when my SAC is usually always under 17l/min. Can't remember when was the last time that we had to cut dive shorter than I promised on briefing. Like last dive I was working, we had 51minutes dive, average depth 15,9m and I used air from 205bar to 45bar. In briefings we tell the customers that divetime is 40-45min (or 50bar)

I've tried larger tank (13,2l) sometimes, but I only get maybe 3-5 minutes extra divetime with that. Of course 5 minutes is a lot in 30-40min dive, but not worth of hassle with carrying your own tank

 

[Tycksel]

Yes some other issue then? This is a DM I dived with in Cebu. He's good on air but he was surprised I am better on gas consumption than he his. He really relaxes diving with me as he doesn't think about me on the dive. He can fun dive with me. Any reason you almost panicked? you need to determine why you would have such anxiety on a dive in perfect confitions on a site you are familiar with.

For me when I am really relaxed my favourite songs and music pop into my head. Other divers have said they can here me humming on my dives when they are really close to me lol I used to play a 4 valve Euphomium and Trombones. You learn as a musician how to extend and control your breathing.

There was actually couple things that might affected to almost panicking:
- I had huge heartburn and I had to vomit after dive. I have reflux but forgot to take medicine before dive
- I didn't trust my divemaster, because I know that he wasn't as experienced than me. But I still know that he knows what to do and even when he didn't know, I know where we are located and how to come safe to the surface and back to the boat.