Overweighted at beginning of dive but underweighted at end in shallows

[NauticalNick]

I assume you were shown how to do a proper weight check during the cert. course. Have you done one with your new equipment?

I had not. I mostly dive on holiday and you know how it normally is, rush, rush, rush to get into the water.

 

[ibj40]

Info - Optimal Buoyancy Computer

The Optimal Buoyancy Computer A tool to help nail buoyancy and improve safety, before you splash 1) How much lead should I carry with my new wetsuit? 2) How big a wing should I buy? 3) Will my BCD support my lead, both at the surface and when my wetsuit is compressed at depth? 4) Will my BCD...

scubaboard.com

Using just a couple of the buoyancy calculators available online, I get results that show 16-20 lbs for a 185 lb male in a full 5 mil suit.

I dive a BARE Velocity 5mm and always request two 4s and four 3s from the dive crew. Slightly overweight but nail the safety stop.

 

[The Chairman]

Learn how to breathe.

People tend to pause with their lungs full. Why not learn to pause with your lungs empty? I do it all the time and have even dove without any bladder on BC. At the beginning of the dive I pause with my lungs full and gradually change where I pause, with less and less air in my lungs as I get to the end of my dive. CAVEAT: Never 'hold' your breath. Never occlude your glottis.

 

[FreqFlier]

but no matter what I did I would just start floating up to the surface on my inhale

Not very many dive profiles end up in the extreme shallows. Anything less than 15' (5m) should be anticipated and properly addressed before the dive (extra weights, different tanks, etc).
As many stated before me, 5mm wetsuit's buoyancy is very different @ 5' compared with buoyancy @ 75' (25m). That's why you seemingly needed a lot of air in your BCD when deep vs shallow. Used up air in your tank exaggerated the issue in the shallows.
With more dives/experience you begin mastering so called diaphragmatic breathing - that helps immensely at any depth, but especially in the shallows. There was a smart guy back in a day, Archimedes was his name. He figured out that your buoyancy is directly dependent on the amount of water you displace, which means the harder you inhale, the more your lungs expand, thus more positively buoyant you become and vice versa. Diaphragmatic breathing allows for less expansion.

 

[NauticalNick]

Learn how to breathe.

People tend to pause with their lungs full. Why not learn to pause with your lungs empty? I do it all the time and have even dove without any bladder on BC. At the beginning of the dive I pause with my lungs full and gradually change where I pause, with less and less air in my lungs as I get to the end of my dive. CAVEAT: Never 'hold' your breath. Never occlude your glottis.

Yes, I'm starting to try doing this but will take some time. I'm not a mouth breather and underwater my natural tendency is definitely to pause after inhale rather than exhale so some things I need to continue work on. I think there is a silly subconscious thing where if I can't draw breath from my regulator I want to have full lungs to figure something out rather than empty lungs. A weird phobia of needing air and it not being there for whatever reason. It's dumb and just something to work on.

Thanks for the note.

 

[The Chairman]

I think there is a silly subconscious thing

The desire to have full lungs will always be there. Always. It's why anxious or scared divers tend to be floaty because the higher your anxiety, the fuller you want to keep your lungs. However, the more you work at it, the easier it becomes. I no longer have to 'think' of where to pause. After decades of working at it, it's become rather automatic... unless I get anxious.

CAVEAT: again, never hold your breath. Keep your glottis open at all times. This allows bubbles to freely escape as you ascend rather than injuring your lungs.

 

[Bento.Box]

Not very many dive profiles end up in the extreme shallows.

"It depends"

For me, it's normal. I dive at our local lakes with natural beaches. I always end up diving along the bottom until the designated exit. Of course you can ascend from your safety stop and swim back to shore on the surface, but then you won't see all the rocks and obstacles that can be a hazard - especially at night.

 

[scubadada]

Learn how to breathe.

People tend to pause with their lungs full. Why not learn to pause with your lungs empty? I do it all the time and have even dove without any bladder on BC. At the beginning of the dive I pause with my lungs full and gradually change where I pause, with less and less air in my lungs as I get to the end of my dive. CAVEAT: Never 'hold' your breath. Never occlude your glottis.

I believe that a short pause after inhalation is more efficient for gas exchange. This is the opposite to normal breathing pattern on land. Do not hold your breath and keep your epiglottis open.

@rsingler ?

 

[hammet]

The only thing I log in my dive book other than date, dive time, and depth is what size and type of tank I was using, wet suit thickness I was wearing, and weight I used. I also indicate if I could have done with more or less weight based on my buiancy at the safety stoop. This gives a great reference for future dives and always gets me within a pound or two of optimal.

 

[FreqFlier]

A weird phobia of needing air and it not being there for whatever reason

It's completely natural. Few more dives later (or few more message board notes later ) you'll figure out that our brain sends a signal to lungs to breathe in not because we are running low on O2, but because of increasing CO2 level in our bloodstream. Takes a while to learn how to slow down your breathing while being aware of brain signals and avoiding panic. Result - better air consumption and easier to avoid panic mode.