Getting Down With Your Buoyancy
By Roee

There are many aspects of diving that contribute to a safe and pleasurable diving experience but one thing that is most often overlooked by divers is buoyancy control. Buoyancy control is the key to an enjoyable and relaxing dive and it is one of the most difficult aspects of diving which differentiates the beginner diver to the more seasoned ones. The first time you might have noticed that buoyancy control is indeed very important and hard to learn was way back, during your first dive in the Ocean with your Open Water class. You have noticed that while most of the students, including yourself, were constantly going up and down and struggling to stay leveled, your instructor was leisurely cruising in the water and occasionally hovering above the students to make sure they were OK.

One of the instructors in my Open Water course, who later became a friend to our entire group, is like a fish (Yes, it's you Joe), consumes very little air underwater and can hover over students effortlessly. I often found myself asking him "How can you use so little air? or "How can you cruise underwater with such grace?". The answer each time is a wicked smile and a simple "It's all about buoyancy control."
Without proper buoyancy control, a diver generally uses more air during a dive, spend more energy, does not fully enjoy the dive because he/she is focusing solely in staying off the bottom or off the surface and invariably disturbing or even damaging the dive site.

Teaching an Open Water student buoyancy control, is one of the hardest job for a scuba instructor. There are so many variables in order to achieve perfect buoyancy such as your weight, equipment, body composition and even the environment. The instructors can only "show" you how it is done but it is up to you to adjust and compensate according to your body and situation. It is a task that requires perfect balancing and tuning of your SCUBA gear and lots and lots of underwater practice.
More than likely you will go through your Open Water training without mastering this skill because lets face it; there simply isn't enough time in this course for your instructor to teach you how to fine tune your buoyancy. Let's see if we can point out a few things that contribute to your buoyancy underwater.

The most obvious place to start is with your key equipment. Wetsuit, BCD, tank and weight belt are your basic SCUBA equipment and will all play a part in your buoyancy. A 3mm single piece neoprene wetsuit will offer far less buoyancy than a 7mm two piece wetsuit.

Your BCD (Buoyancy Compensator Device) is mainly responsible for keeping you afloat on the surface and also giving you a way to fine tune your buoyancy while underwater by inflating the bladders in your BCD with air. When choosing a BCD, try as many as you can since there are different types of BCDs such as jacket style or back inflation and they all function and react differently from one another. The most important thing however is to choose one that fits you comfortably and securely. A loose or overly tight BCD can create all sorts of problems during a dive. One thing that is very common among students in the Open Water courses is to surface by inflating their BCDs. Keep in mind that your BCD does not serve as an elevator. Inflating your BCD to surface is not the correct way to ascend and may cause you to ascend too rapidly or to miss your safety stop entirely.

Tanks are also responsible in part for your buoyancy. The most common types of tanks are the aluminum and the steel tanks. Aluminum tanks are negatively buoyant when filled and positively buoyant when empty and can pose a problem for your buoyancy if you take off some of your weight to compensate at the beginning of the dive and because of that you will experience the positive buoyancy effects as you consume the air in your tank making buoyancy control very difficult in the last part of your dive.
Steel tank in the other hand are generally negatively buoyant when full, and neutrally or slightly negative buoyant when empty. In order to achieve good buoyancy control, you should always factor in the effects the tanks will have.

Many divers have problems breaking the first 5 ft of water and descending to their dive spots and compensate this problem by adding more weight. That is definitely not the way to go because after they have descended, they are now constantly struggling to stay off the bottom and counter that problem by adding air into their BCDs and effectively ruining their chances in achieving good buoyancy control. The amount of weight you should carry during a dive is the amount that can make you neutrally buoyant at around 10 to 15 ft because this is the depth that you will be doing your safety stops and you will want to be neutrally buoyant during this task.
Other common SCUBA equipment such as fins, camera, and light will also influence your buoyancy underwater. Always keep that in mind when attempting to optimize your buoyancy.

The diver's position in the water and weight distribution is also very important during a dive. The trim (your body angle in the water) will determine how much resistance you will encounter from the water, therefore, also determining the amount of energy and air you will use.

There are several techniques in practicing your buoyancy control and body positioning, but the most common one is called the Fin Pivot. This exercise was taught by your Open Water instructor during your first pool session and is achieved by laying flat on your stomach in the bottom and adding just enough air in your BCD to have your upper body slightly float up and down with just your breaths. If you can easily perform the Fin Pivot, you are that much closer in achieving your desired buoyancy control.

Another way to help you with your buoyancy control is to modify your equipment. For example, if your legs tend to sink when you are in the water, altering the position where your tank is strapped to your BCD might shift your weight so that you can more easily swim horizontally underwater. You can also distribute the weight throughout your body more efficiently and according to your natural body position or by switching your fins and boots to a more buoyant set.

Buoyancy control is one of those skills that you have to practice and improve upon all the time. With some practice, you will soon realize the advantages of having good buoyancy control during a dive. You will use less air and less energy providing you with longer, more relaxing and safer dives. There are courses that specifically tackle the buoyancy control issue. If you are in the Los Angeles area, stop by the La Canada Sport Chalet and talk to Joe. Ask him about how you can stay longer and use less air in a dive. He will reply with his all too well known "Is all about your buoyancy control" together with his patented wicked smile.