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drk5036

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I said “should have,” not “would have.”

Edit: OK, let me spell this out some more for the person who was confused by my post. "Should have" because if someone is properly weighted, then losing weight means going up. Not "would have" because if he's overweighted then perhaps it would not.
but this isn't correct. if you're carrying 6 pounds of air in your tank, you need to be 6 pounds heavy at the start of the dive so that you can maintain your safety stop. That means adding 6 pounds of air to your BCD that you will remove throughout the dive. If he lost his weight pocket that contained 3 pounds of weight, he would only need to add 3 pounds of air to his bcd to be neutral, at the beginning of the dive. The problem would occur after 3 pounds of air has been used, when he wouldn't be able to main neutral buoyancy.
 

lowwall

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I’m very pleased with the Mares Prestige as opposed to the Hollis HD 200. Easy to make trim at depth and surface. Maneuverable, lightweight and durable, however, right side Integrated weight slipped out without my knowledge until I saw it at the bottom of the training pool. Other than that I am happy with my choice of BCD.
Make sure you give a good tug on your weight pockets to check if they are really clipped in. Mares BCDs are no better than average when it comes to integrated weight retention.
 

Belzelbub

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I said “should have,” not “would have.”

Edit: OK, let me spell this out some more for the person who was confused by my post. "Should have" because if someone is properly weighted, then losing weight means going up. Not "would have" because if he's overweighted then perhaps it would not.
It really depends on when the loss of the weight pocket occurred. If it occurred during descent, the diver is negatively buoyant, and the tank is likely near maximum negative buoyancy. In this case, it's unlikely that a lost pocket would result in a shift from negative to positive buoyancy.

Now, if the diver had already established neutral buoyancy, a lost weight pocket will result in positive buoyancy. However, depending on how much weight was lost, and the current buoyancy characteristics of the tank, the diver could most likely vent a little air and be back to neutral. That should probably be a clue that something is off, though.

Toward the end of the dive, loss of a weight pocket on a properly weighted diver will cause the diver to go up. At this point, tank is at it's most buoyant (low negative or positive buoyancy, depending on tank), so a properly weighted diver would not have enough lead to counteract buoyancy.

Of course, it would also depend on what the total ballast was, and how much of that total was now lost. In the case I mentioned earlier where I forgot to zip my weight pocket, I would guess that my total weight at that time was probably 10 lbs. 3 lbs in each Ripcord pocket, and 2 in each trim pocket. Early in the dive, and relatively small amount compared to total, so had I not seen the weights on the bottom, it's unlikely I would have noticed until much later.
 

pauldw

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OK, my mistake, I usually have a lot more than six pounds of weight.
 
https://www.shearwater.com/products/swift/

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