A recent discussion in the comments of an article of weight was a bit of an eye opener. Comments ranged from “it’s not rocket science” to “I’d rather be overweighted”. There were also many comments on PADI, and their instructors, being about making money but I’ll leave that one for another day.
You have to consider why we wear weight. If we were pulled down to depth how much weight would be needed? So is the weight just to get down and then stay down (although we need less to stay down than we did to get down). Remember the basic physics you learned when learning to dive and the effect that depth has. The effect of weight at the surface is increased as you dive deeper.
So does it matter that you’re carrying an extra 4kg? Yes. I think it does. The increased weight may get you down a bit quicker but it then it becomes a massive hindrance at depth. Remember the pressure increases by 1 ATA (or 1 bar) every 10m. Your suit will compress and that will lead to the need for less weight anyway. We don’t dump weight as we descend but we do add air to our BC to compensate.
You are then at depth having to work to overcome the effects of that extra lead. This leads to increased air consumption and an unnecessary additional effort that your body has to make under the water. You often see divers finning to keep themselves at a level depth. With additional weight you will need to fin more to ascend, or relatively over inflate your BC.
All of this may seem a bit of a fuss for the sake of a couple of kilograms. But you’re investing a huge amount of money and time into a sport that has inherent risks. Why not take a few minutes a day to actually check your weight? I can’t see the fuss in the forums about spending time on something that will enhance your dive experience, and increase the safety aspect of your dive.
So. How do you go about getting the right weight? Doing a weight check is a great start. Estimate the amount of weight you need and then empty your BC, hold a normal breath and you should hover at eye level. You can then add or remove as you need. Having a buddy with clip on weights at the boat is a great help!
Log dives. Note down what suit you were wearing and salt or fresh water.
Don’t add weight just to descend. Relax at the surface and empty your lungs. You’ll go down. And if you think you’ve emptied your lungs then try again – there will be more air in there! Don’t then take a massive breath and refill the lungs when you’re 50cm under the surface though!
Take the descent slowly. There is no rush. Just ease yourself down. Because of physics you know that the slowest part of the descent is at the surface. You would then accelerate the deeper you went if it wasn’t for compensating with the BC. Relax. Have a bit of patience.
And yes. I recommend the Peak Performance Buoyancy course. And not to make money (I’ll blog about the millions I make as an instructor in another post!) but because buoyancy is key to safety, enjoyment and marine conservation.