Buoyancy Issues

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ScubaWithTurk

Bubble Blowing Buddha
Scuba Instructor
Messages
1,338
Reaction score
1,443
Location
Amed Bali
# of dives
2500 - 4999
I have been struggling with finding neutral buoyancy. On my OW training dives I had issues with popping up like a cork and bouncing off the bottom (luckily in a sandy area.

So I went to my friend's pool over the weekend and tried to do some work on this only to have even more issues. I know that in a pool that is only 9' deep max it can be hard to stay neutral but I was either bouncing off the bottom or basically sitting at the surface with my tank almost out of the water.

I go down to depth and add a little air in my BCD. I felt neutral but as I would exhale I would hit the bottom and then upon inhaling I would pop up.

I did notice I had some air trapped in my BCD and using the manual deflate button didn't help so I had to use the shoulder dump as I angled my left shoulder down. This helped but I would still pop up.

I am at a loss as to what I am doing wrong here. Could be my weighting or could be I am just terrible at diving. Which I hope isn't the case but at this point I am seriously questioning my ability to dive and dive well. (side note: I am my biggest critic and know it is a big fault of mine as I can be very hard on myself)

I have a three tank dive trip this Sunday to the West side of Catalina and was hoping I could get some tips, pointers or suggestions from the more experienced divers and instructors out there.

I wear a 7 mil wet suit, 5 mil gloves (which I hate and have little to no dexterity in but that is another thread), Deep 6 fins, weigh 189 lbs and currently have 26 pounds of weight. 18 lbs in my BCD integrated weight pockets with 4 pounds each in my trim pockets.

If I forgot any details you may need to give me tips please let me know.

Thank you all for helping me through this journey. From prior to my OW class to know I have had some great advice and look forward to more.
 
I can most definitely relate. I really need to do a lot more work on breathing and that's what I'll focus on during my dives this weekend.
 
I can most definitely relate. I really need to do a lot more work on breathing and that's what I'll focus on during my dives this weekend.


I need to do the same.
 
If you are sinking on exhale and rising on inhale then your buoyancy is ok. What you need to do is to begin exhaling as you begin to rise and inhale as you begin to sink.

Since you have inertia, you will find that your body will only move slightly. By the time it wants to go up, you're already on the bottom part of your lungs.
 
If you have a lot of air in your wing in shallow water it's easy to get into a bad cycle. If that's the case you are overweighted.
 
Slow down your breathing. Never close off your throat, but don't pump complete lungfulls in and out all the time. I've this problem, too, though mine's from having swimmer's lungs and training. I need to make a conscious effort to not breathe like I'm doing a one-minute hundred every time I hit the water. Anyway, try slow breathing into your lower abdomen, yoga/martial arts-style. My better half often goes "auhmmmmm".
 
You need to be dealing with issues when they are minor by using minor changes to your wing. Add or release a little air when you notice a minor change. Don't wait until to react until you are plummeting into the depths or imitating a Polaris missile. At that point you need to make drastic changes and they won't work cleanly. Jamming on the inflate button as you plummet WILL stop you from sinking to the bottom, but you will then start a rapid rise to the surface. Then you start to vent the wing, but over-vent and start to plummet again...

You need to dive your rig, not let it dive you.
 
If you were OW certified, and you feel that you are still having buoyancy issues, first I'd go back to the instructor and tell them you don't think you quite have that down, and see if they'll let you join in a pool (or open) session for some more attention to that. Which really should be FREE because it should have been done the first time around.

But consider this: Did they go over what your lung volume is? The tidal volume when you are breathing, and the total volume in your lungs? If you are new to scuba you may be unconsciously taking bigger breathes, and that will mean several pounds of buoyancy change every time you inhale and exhale. Hmmm...

Lung volume can be six liters, tidal volume as little as 1/2 liter. Fast metric system conversion, one liter of fresh water weighs 2.2 pounds, so your lung volume can be a 13# change. Your tidal volume, a 1# change under optimal conditions, maybe more like a 3-4# change if you are deep breathing. I'm not suggesting this is the whole issue, just that calm breathing will help. (Someone else can argue how shallow that breathing should be.(G)

You should be able to get in the pool, all geared up, with some extra lead (or bricks, whatever) and trim out so you are hovering just above the bottom, rising and sinking a bit with each breath as that tips the balance. Some patience, some practice, some coaching (oh, wait, they call that a GOOD INSTRUCTOR!) and you should get the hang of it.

Patience. Practice. Experience.

And then of course, a full tank and an empty tank can have a significant difference in buoyancy as well, so if you are trimmed right at the start of a dive? You may need (with an Alu80, you WILL need) more weight by the end of the dive.

Take your time, you'll get the hang of it. No real way to rush it.
 
In the pool all gear on, bc empty, half a lungfull of air you should float with your nose at or just under the water. Use your snorkel and try to remain motionless. You might need to add a pound or two in the ocean due to sg difference to pool.
 

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