Huge air consumption even after +200 dives

[jellycatsdad]

P.S., trying out the AI on my fancy new phone here.

When I first started diving, I would spend 20-30 minutes (I believe my SAC was 60psi/m) sucking down a Al/HP80, sculling the water, and feeling anxious. Over a year later, I’ve made significant progress. I’ve improved my buoyancy (although I still need to work on trim), set up a more stable kit, and now, with an HP100, I’m approaching the 1-hour mark on dives. My SAC has dropped to the low-20s.

While cardio can be beneficial for scuba, yoga offers much greater advantages. Ultimately, the key is to feel comfortable in the water, achieve good buoyancy and trim, and avoid sculling the water. This way, you can slow down, enjoy the scenery (or spot nudis or other creatures), and truly immerse yourself in the underwater experience.

Oh, I’m 190lb/87kg and 5’8”/175cm.

 

[Tycksel]

Updates. Air consumption is still not where I want that to be. On a very relaxed dive, it's around 15-16L/min but typically it's been 17-18L/min, when there's little current, bad viz, not so familiar customers etc.

There was little peak in the start of February, because I suffered ear infection and wasn't underwater for 1,5 weeks. Also updated my 3mm wetsuit to 5mm, and also had to increase my weights from 2kg to 6,6kg. Now I have 3,6kg.

I've tried different breathing patterns like 3sec in - 12-15 sec out, keeping my tongue in top of my mouth etc, but nothing helps. I think this is in my head. Like if I stress about current, air consumption, viz, navigation, leaking mask etc, my air consumption increases.

Still sometimes customers ask that why we cut out dive so short because they still had air, and it's so embarrassing to answer that because I, divemaster, didn't had enough air

 

[Wibble]

Updates. Air consumption is still not where I want that to be. On a very relaxed dive, it's around 15-16L/min but typically it's been 17-18L/min, when there's little current, bad viz, not so familiar customers etc.

There was little peak in the start of February, because I suffered ear infection and wasn't underwater for 1,5 weeks. Also updated my 3mm wetsuit to 5mm, and also had to increase my weights from 2kg to 6,6kg. Now I have 3,6kg.

I've tried different breathing patterns like 3sec in - 12-15 sec out, keeping my tongue in top of my mouth etc, but nothing helps. I think this is in my head. Like if I stress about current, air consumption, viz, navigation, leaking mask etc, my air consumption increases.

Still sometimes customers ask that why we cut out dive so short because they still had air, and it's so embarrassing to answer that because I, divemaster, didn't had enough air

Seems that you’re just a heavy breather. Maybe accept this and use equipment to mitigate this.

Is there any chance that you could dive with more gas? You could:

• use a steel 12 litre;
• a steel 15 litre;
• add a pony, ali40, ali7 or ali80;
• dive sidemount with 2 ali80s;
• dive a twinset (a.k.a. “twindies”) with two individual single Ali-80s — backmounted sidemount! — meaning you can breathe one down and switch to the other.
• Even dive a full manifolded twinset, although this would cause logistical grief in most recreational divemaster settings

There’s a ton of options that will help you out and possibly relax you in the water. There’s nothing like the worry of running low on gas to add yet more stress and concern, especially as you’re the “dive professional” calling the dives early.

 

[Agro]

Seems that you’re just a heavy breather. Maybe accept this and use equipment to mitigate this.

Is there any chance that you could dive with more gas? You could:

• use a steel 12 litre;
• a steel 15 litre;
• add a pony, ali40, ali7 or ali80;
• dive sidemount with 2 ali80s;
• dive a twinset (“twindies”) with two individual single Ali-80s — backmounted sidemount! — meaning you can breathe one down and switch to the other.
• Even dive a full manifolded twinset, although this would give logistical grief

There’s a ton of options that will help you out and possibly relax you in the water. There’s nothing like the worry of running low on gas to add yet more stress and concern, especially as you’re the “dive professional” calling the dives early.

Your sac is low! You are a 120kg guy, I don't expect a lower sac to be possible in your case.
Of course it increases a littel bit when diving with customers, this is littel bit of stress.
You dive a wing, so you have a backplate? I hope you can just add two 80s, independent doubles, problem solved and some extra safety.

 

[scubaozy]

Just buy 2 x 15l steel tanks, assuming you are offering 2 dives charter and use your private tanks for work. Additional 3l will even out the disparity between you and average customer.

 

[CG43]

I've tried different breathing patterns like 3sec in - 12-15 sec out, keeping my tongue in top of my mouth etc, but nothing helps. I think this is in my head. Like if I stress about current, air consumption, viz, navigation, leaking mask etc, my air consumption increases.

You can eliminate one of the stress factors immediately and thoroughly, the fear of excessive air consumption. Use bigger tank or tanks .
Man you are a pro : you must always have enough air in reserve for a student .
You are not a girl of 47 kg therefor you can carry a little more.

breathing patterns like 3sec in - 12-15 sec out, keeping my tongue in top of my mouth etc,

Four breaths per minute is a good value. At 16 l/min this results in a tidal volume of 4 l which is also very good. But can you really exhale loosely and relaxed for 12 seconds ?
So not if you pay attention to it, but automatically without awareness of it?
Anything that does not work automatically cannot work in the long run.

You breathe out 12 sec. long.
I forget to breathe after inhaling until the CO2 stimulates me to exhale.
How long that takes depends on the circumstances, so I don't have to take care of it.
Since the CO2 hits a large lung volume, the concentration does not rise very quickly, so that a low air consumption is automatically the result.

 

[SouthernSharktoothDiver]

@CG43 I hope you don't mean you're holding your breath on inhale, as that can be rather dangerous.

@Tycksel I recall you saying you had difficulty getting bigger tanks because of what's available in your in area, but have you considered diving double AL 80's? That way you can use the standard tanks, and still have plenty of air. It'd add a lot of surface weight, but as have previous been mentioned, you're a big guy, so you should be able to lift that much, just lift with your legs. Or alternatively, consider sidemount, or perhaps an al 40 pony.

 

[Tycksel]

I really hope to solve this problem without buying tanks every winter, and also travel with tanks... If I would dive in my home country, yeah I definetely would buy double tanks or at least bigger tank.

I work winter times in south-east Asia and I've never seen steel tanks anywhere. Also 15L alu tanks are super rare, and like I said before, they removed those from my current working boat too.

We use same tanks (12L alu), like all the students, customers, instructors etc. Nobody has own tanks. I've never seen anyone diving with doubles and we are not allowed to work with sidemounts.

 

[Tycksel]

You can eliminate one of the stress factors immediately and thoroughly, the fear of excessive air consumption. Use bigger tank or tanks .
Man you are a pro : you must always have enough air in reserve for a student .
You are not a girl of 47 kg therefor you can carry a little more.


Four breaths per minute is a good value. At 16 l/min this results in a tidal volume of 4 l which is also very good. But can you really exhale loosely and relaxed for 12 seconds ?
So not if you pay attention to it, but automatically without awareness of it?
Anything that does not work automatically cannot work in the long run.

You breathe out 12 sec. long.
I forget to breathe after inhaling until the CO2 stimulates me to exhale.
How long that takes depends on the circumstances, so I don't have to take care of it.
Since the CO2 hits a large lung volume, the concentration does not rise very quickly, so that a low air consumption is automatically the result.

I just tried that 3sec in, 12-15secs out for couple of dives. But then I quitted that, because it felt so uncomfortable and my sac didn't get any lower. My relaxing "natural" breathing in underwater is around 4sec in, 8sec out

 

[therookie]

Hi @Tycksel

Learning to breathe underwater really isn't easy, is it?

You have more in-water experience than I do, and much more training, so I don't want to say too much. But, a few things come to mind from my own learning experience with breathing from a cylinder...

- How long have you been a professional? If your total dive count is ~250 I'm thinking it's still early in your career. DMs where I am are usually doing at least a couple of tanks every day, at least 5 (sometimes more) days per week (unless it's low season). So depending on how you define "winter" (where I grew up in northern Canada it is arguably six months out of the year, and friends living in Finland tell me it's a similar climate!) that adds up very quickly. I ask this because for me if I am under any stress at all my SAC rate is significantly higher, and it could be that if you are still new to being a divemaster you will find your SAC rate decrease as you gain experience and find it less stressful... If I were a DM right now my gas consumption would be through the roof!

- It probably isn't what dive professionals want to do on their days off, but when you are working in SE Asia do you have opportunity or inclination to do any "fun dives"? Like, where you aren't the one responsible for a group - maybe just a dive with a buddy in conditions similar to what you are diving as a pro. And not that you should spend those dives focusing on your SAC rate, because that will defeat the purpose. Just a dive purely for fun. In that case, what is your SAC rate? If you could measure that you would have a "baseline" for that environment that you could then use for comparison against your "working" SAC rate.

- Gas consumption is (logically enough) not just a matter of breathing rate but also breathing volume. For me I need to be be somewhat conscious of not taking in too much gas when I inhale. I remind myself of that on the boat before I splash (it's all boat dives here) and again at the surface just before I descend. And even still, sometimes I find myself feeling that "significantly up when I inhale / back down when I exhale" sensation that you described earlier, and it tells me (at least I think it tells me) that I'm taking in too much gas in my inhale. When I consciously tamp that back down, that sensation goes away, and my body doesn't feel like it's "starving for air". It can happen frequently during a dive because I still don't have nearly enough dives yet to have the "muscle memory" to instinctively know how much gas to inhale, so it requires a bit of thought - from time to time, without obsessing over it because that invariably kicks my SAC rate up again.

- Do you have an AI computer? I don't, but one of the advantages I could see to owning one is that it tracks your gas consumption throughout the dive, and being able to review that afterward might show you useful information - like generally your SAC rate is fine but there are moments in the dive where it spiked, which you can then maybe relate to something that occured during the dive (could be positive or negative) that caused the spike. Of course, my understanding is that DMs don't get paid a whole lot for their services so if you don't have an AI computer that might be too much of an investment at the moment, but it might give you a place to look.

Just a few thoughts from one less experienced than you...