Is this a weight problem? or am I close?

[DougK]

I am a newer diver with 8 dives under my weight belt. I am having some on-going weight problems but seem to ge getting it under control. In my training I took a lot of weight --between 22 and 30 lbs-- to get to the bottom of the pool -- more weight than I am using to dive in the ocean. I am sure this was due to nerviousness, however my instructors told me as a guy 200 lbs and 6 feet tall, I must have large lungs.

In the ocean I am down to 16 lbs and doing better, HOWEVER when my air tank gets low I find I have a harder time staying down at depth when swimming horizontaly. I notice I am rising in the water column. On my last dive, I found even with the air tank low I could swim to the bottom, but not stay down without a little effort. As a test I pulled up vertically in the water and was able to sink to the bottom in about 30 feet landing on a sandy area. When doing my safety stop at 15 feet, we had a photograher shooting video of the dive and for a moment I was watching her and not my depth and noticed I sank back down to the bottom. (I was using a 3mm shorty and rented gear., but had the same problem on an earlier dive to 50 feet.)

Am I getting my weigh close to where I need it? Even with the low-air tank problems, if I can sink to the bottom am I just about on the mark with the amount of weigh I am using? ** At the beginning of the dive I needed no air in the BC to stay where I wanted to be and that included the bottom.

Would anyone recommend anymore weight at this time?

 

[tomcat]

you sound like you are doing tropical diving. since it is a 3mm suit, even 20 lbs is way too much. this is taking into account your height and weight. you should be able to get down to about 10 lbs eventually. with loads of experience and comfort in the water, 4-6 lbs might be the final steady state for you.

if you are low on air and you can sink in 10 ft of water, it is evidence that breathing is a big factor in your buoyancy here. new divers who are anxious tend to not fully breathe out with each cycle. therefore, lungs tend to be more filled on average, increasing buoyancy and need for weights.

the way to tell if you are properly weighted is to get into the water with a full tank and empty your bc. with half to a full lung of air, you should still be floating (even if it is just the tip of your head touching the surface). when you breathe out fully (i mean really really empty your lungs), you should start to sink.

if there is no way that you can stop yourself sinking with an empty bc while at the surface, then you are overweighted. drop weights until you can stop yourself from sinking with half to a full lung of air.

 

[MechDiver]

If you're still negative at the end of the dive with a low tank, I wouldn't see any reason to add weight.

Breathing rate, as well as weight needed will improve as you gain experience and comfort. Don't let either become an issue, just dive and relax. The rest will come in time.

MD

 

[Sideband]

I'm going to preface this with, you have more experience than me, but...
You should do another buoyancy check and this time do it with an almost empty tank. The goal is to end the dive as neutral as possible. If you are ending the dive positive then you may need a tad bit more weight. Since you mentioned that when you were not concentrating on keeping your depth you began to sink, leads me in a different direction. What probably happened is you stopped concentrating on what you were doing and therefore relaxed a little. As you relaxed your breathing became shallower and you lost buoyancy.
CONCLUSION:
You are probably weighted just about right and as you get more comfortable you may be able to drop a LB or two. In the meantime you may need to add a lb or two. Wait for other replies before adding any more though because I don't feel comfortable suggesting that. I do highly recomend the new buoyancy check with an almost empty tank though.

I hope that was helpful and accurate. Hopefully others will either back what I said or set me on fire and watch me burn. Either way we will both learn something from your question.
Safe diving.

Joe

 

[neil]

Am I getting my weigh close to where I need it? Even with the low-air tank problems, if I can sink to the bottom am I just about on the mark with the amount of weigh I am using? ** At the beginning of the dive I needed no air in the BC to stay where I wanted to be and that included the bottom.
Would anyone recommend anymore weight at this time?

Your instructor wasn't sure that bigger people have bigger lungs?
Basically you have it right. You need only enough weight to keep you under water with an empty tank. If you want to add a little extra for now to account for your large-person/newbie breathing pattern, it wouldn't be such a bad idea. A guy your size (and mine) can easily add 5 lbs of lift by taking a big breath UW. That's a lot. You need to get your breathing under control more than anything. And never, NEVER get excited UW. :^)

Neil

 

[Boogie711]

Get in the water with a near-empty tank and see how much weight you need to stay neutral just under the water. BUT - do it with empty lungs, and DON'T move. Cross your ankles over to avoid finning. Keep your hands still. Take little breaths.

With 8 dives, it just sounds like you're "nervous" in the water (maybe not in your head, but nervous as in fidgety and moving around a lot.) That will throw off your SAC rate, your breathing, everything. Just try to have a nap.

 

[DougK]

To clarify, I was diving off Mexico. When I said I could stay at the bottom with no air in my BC at the beginning of the dive, I meant to say netural NEAR the bottom. Not standing on the bottom or bumping on the bottom.

I have done an extensive weight check and did it with low air in the resort's pool. The amount of 16lb was the amount the Dive Con and I arrived at after this check compensating for salt water. I was using less in the pool and could rise off the bottom of the pool with one breath. The situation I described in my first post was the experiences I had after the weight check.

 

[mjh]

Agree with Neil work on your breathing. Like you I'm 6' about 200lbs and with a full 3mm in Mexico I was diving with about 4lbs. Now there are a lot of variables, gear, body compostion, etc... but relaxing and breathing evenly will help a lot.

 

[perpet1]

You seem to be doing fine. and I am sure with a little work you will figure it all out.

There is a common theme to the responses here and that is to do your bouyency checks should be done with a nearly empty tank (500psi is ok).

The reason for this is simple in that air in your tank adds weight. As you breath this air the weight of the air in your tank decreases (there is afterall less of it). You can assume about 5 pounds for an 80 give or take. That is to say at the start of a dive you should be about 5 pounds negative if you want to be neutral at the end (where it really matters as that is where you need to control an ascent).

 

[freedive]

Yes BREATHING and RELAXING have to be the two most determining lead factors. When I started last year I was using all of 16 Lbs of weight. I'm 6'1" and 225 Lbs diving in S Fla with a 3mil Shortie. Today after 28 dives I'm down to 10 Lbs with the same equipment. Hopefully this summer I'll bring it down to a steady 8 Lbs.

regards,
Juan