Buoyancy

Have you ever been scuba diving, watching as schools of fish swim by you through branches of coral as you swim through perfectly blue water, feeling totally weightless and free of gravity? That’s what it feels like to go scuba diving being neutrally buoyant, you’re perfectly balanced between the air in your BCD that makes you positive buoyant (float), and the weights on your belt which makes you negative buoyant (sink).

Buoyancy is governed by Archimedes principle, which states that an object immersed in a fluid will float if it weighs less than the amount of water it displaces and will sink if it weighs more than the amount of water it displaces. This means that in order to achieving neutral buoyancy is a bit of a balancing act. To test your Buoyancy gear up as normal, and once you are in the water on the surface with your regulator in your mouth, deflate your BCD completely and then hold your breath. If you’re properly weighted, you should float with the water at eye level and when you breathe out you should start to sink easily.

So how can you fine tune your buoyancy?

It’s important to consider your equipment when you’re weighting yourself. All wetsuits are slightly buoyant already due to air trapped inside their layers. The thicker the wetsuit is, the more Buoyant the wetsuit already is by itself. Steel cylinders are less buoyant than aluminium ones because the walls inside the Steel cylinders are thicker and more rigid there they don't change there buoyancy as it becomes empty and as for the Aluminium cylinders the walls inside are more flexible and thinner they become more buoyant as the cylinder becomes empty.

Depth also influences the buoyancy of your equipment. The deeper you go the air you have in your wet suit and BCD will compress, and you’ll lose some buoyancy. It’s important to keep this in mind because you want to avoid a sudden increase in buoyancy as you start to resurface. It’s unpleasant to have to forcefully swim down in order to get your safety stop in. And if you change your equipment, it’s always a good idea to perform a weight check.

The way you breathe actually has the ability to affect your buoyancy as well. In order to have good buoyancy control you’re going to want to practice slow and relaxed deep breaths. Breathe slowly using your full lung capacity, and you’ll remain calm. If you’re stressed there may be sudden changes in your breathing which can create inconsistent buoyancy.

The way you’re positioned in the water is also important in terms of maintaining a neutral buoyancy for a safe and enjoyable dive. Ideally you want to be horizontal as possible with your head up looking forward and arms stretched out and having a slight arch in your back keeping tension in your hips so your legs slightly above your head in a 90 degree at thigh and calf.

Buoyancy skills, like any other take a lot of practice in order to master so don’t be discouraged if you can’t get it first, second or even third try. You’ll require patience, perseverance, and plenty of practice, so don't be discouraged if you don't get it right away.

To achieve neutral buoyancy it takes a combination of multiple different techniques and strategies but if you manage to get a neutral buoyancy you’ll be able to glide effortlessly through the water. This not only conserves your air supply but also helps preserve the beautiful underwater world we like to explore so much.