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Dive Like a Pro: Let’s Talk Neutral Buoyancy Control


Pop quiz!

For a minute, let’s go back to chapter 1 of your PADI Open Water course. What is neutral buoyancy control? It’s that amazing feeling you hope to achieve while scuba diving that brings us as close as we will ever get to being astronauts. Neutral buoyancy occurs when an object’s weight is equal to the fluid it displaces. Therefore, the object neither floats nor sinks. Why are we on the subject of neutral buoyancy you ask? At the risk of sounding like a jaded dive instructor, I simply see too many certified divers with inadequate buoyancy control to keep these thoughts to myself any longer. In this short tutorial blog, we are going to discuss how to achieve proper neutral buoyancy. Usually, access to insider tips and tricks comes at a cost, but today I am releasing some serious knowledge with the hope that divers will read this Blog and put these methods into practice. As visitors to a very delicate environment, it is our responsibility to leave a dive site the way we find it. This all starts with good buoyancy habits.

neutral buoyancyTip #1: Dive Properly Weighted

Divers have to use lead weights to sink. The amount of weight you need is dependent upon your weight, the thickness of your exposure suit, even muscle density plays a factor. The more you weigh, the more weight you will need. The thickness of your exposure suit greatly determines how much weight you will need as well. Someone diving in tropical water in a 3mm suit will need less weight than someone diving in the Pacific Northwest in a 7mm wetsuit. The air pockets in neoprene add an immense amount of buoyancy and therefore a 7mm wetsuit requires substantial extra weight. I often find that divers trained in cold water with the burden of thick wetsuits and more gear, typically have more advanced neutral buoyancy control than divers trained in temperate waters. The practice in cold water with a lot of weight forces good buoyancy habits. But you don’t have to be a cold-water diver to learn good buoyancy control!

The most common mistake we see is people diving with or requesting too much weight. Diving with extra weight will no doubt make you sink easier, but various habits are formed by diving overweighted. First, the bottom half of your body tends to tilt downward. If you are diving close to the bottom then your fins will kick up the sand behind you. This not only obstructs the visibility of scuba divers behind you, but it also disturbs the sea life living in the sand. The best game you can play while diving is to see if you can make it through an entire dive without touching or grazing ANYTHING. Including the sand. If you are swimming higher in the water column with your legs tilted downward it may cause you to “yo-yo” dive. Since your legs are beneath you, you end up picking up with each kick instead of kicking forward. This counteracts the lead weights pulling you down, but it is an incredibly inefficient way to move in the water and will cause you to use the air in your tank much faster. Not only is your kicking inefficient, you will undoubtedly have to rely more on your BCD to achieve neutral buoyancy, and this also wastes your air.

Be sure to do a buoyancy check at the surface before you begin your dive. With an empty BCD and a holding a normal breath you should float at eye level if not slightly below. If you have an empty BCD and are floating far below the surface as you hold your breath then you need to remove some weight. If you are floating above the surface with an empty BCD and a normal breath held then you need to add some weight. Diving with too little weight is very tiring as you compensate with your breathing and kicking in an attempt to keep yourself down. This is by far the hardest way to dive and should be avoided at all costs. There is no shame in having to dive with more weight. Comfort is key!

buoyancy control

Tip #2: Lungs and Legs!

You will hear multiple times from Banyan Tree Divers instructors our famous Lungs and Legs reminder. Once you descend, your breathing and kicking control your neutral buoyancy. The closer to the surface you are, the more buoyant you are, so it is not uncommon to begin a dive feeling like you aren’t sinking easily. The trick is to stay vertical with your feet down and completely deflate your lungs. A short inhale followed by another long exhale will get you down that first few feet.

Once you have started your descent you must position your body horizontally in the water. Remember, you don’t want to keep swimming with your legs down and start yo-yo diving. It doesn’t look cool at all! When you dive you should almost feel like your feet are above your head as they extend behind you. Long kicks from your hips with knees slightly bent will allow you to move efficiently. If you can frog kick that’s even better. However, diving is not about moving fast. The less work you do to swim the longer your tank will last. Move slowly and efficiently.

Using only lungs and legs also means keeping your arms still. Often at the beginning of scuba diving people feel the need to steady themselves with their arms. This is quite natural considering that we learn to swim with our arms. However, if you watch a diver with impeccable neutral buoyancy control, you will notice that he or she NEVER uses arms for swimming or stabilizing. Diving with your arms is not only inefficient (looks uncool) and wasteful for your air consumption, it increases the risk of you smacking your buddy or worse, smacking a sea urchin. Keep your arms tucked in and only use your Lungs and Legs!

Your breathing is perhaps the most important aspect of neutral buoyancy control. We all learn in Open Water that when you inhale you rise slowly and when you exhale, you sink. Your entire dive is an exercise in controlling your breathing to maintain the depth in which you prefer to dive. Fast, shallow breathing will pull you up toward the surface. Exhaling fully if overweighted without compensating with your BCD will cause you to crash into the bottom. That’s assuming you have a bottom to crash into. Often dive sites are hundreds of feet deep and without monitoring your depth gauge, it is quite easy to dip below recreational dive limits without even noticing.

neutral buoyancy control

Tip #3: Awareness

I cannot stress enough how important it is to be aware throughout your dive experience, whether above or below the surface. This is not only for safety reasons but also for how we achieve that perfect neutral buoyancy control. On the surface, you want to be sure to stay close to your dive leader with your BCD fully inflated. He or she is often trying to get to a specific descent area, and if you are swimming in current far away, then others have to wait for you to catch up.

Use the aforementioned technique to descend as you maintain eye contact with your dive leader and your buddy. Your dive leader will be trying to ask if you are okay. If you or your buddy have ear issues upon descent it is important to communicate that immediately so that the group doesn’t continue until everyone is ready. If you have to wait for other people to get down, try to practice hovering with your breathing instead of sinking to the bottom. With that said, stay close to your dive leader. If there is current, then the bottom might be the safest place to wait for other divers.

As you move along the coral pick visual references. Tell yourself that you are not going to rise above or below your visual reference. If your body is positioned properly then your breathing should do the rest of the work. If you start to sink take a big breath. If you start rising above your reference then exhale fully. After a while, your eyes will naturally pick references that keep you aware of where you are in the water. This is not only important for maintaining neutral buoyancy, but it also keeps you focused on having zero contact with the reef.

Unfortunately I can’t count how many times I have seen unaware divers crash into the reef during an uncontrolled descent, dive too close to the coral or seafloor and kick them with their fins, bang into the coral with their tank from attempting to swim backward without full awareness, use live reef to steady themselves to look at something small or take photos, the list goes on and on and pertains to dive professionals as well as recreational divers.

buoyancy dive

Final Thought:

According to a study done in the Philippines, each scuba diver has on average 10 interactions with the coral during a single dive. If you think about each day that thousands of divers worldwide explore thousands of dive sites, that is a lot of tampering with delicate and finite coral reefs. Reef systems around the world are in serious peril, and by that, I mean their complete annihilation within the lifetime of those born in the early 2000s. With 90% of the planet’s coral reefs expected to die by 2050 (see reference), it is up to scuba divers to be ambassadors for the underwater world. Each scuba dive is an opportunity to be a great example of buoyancy control. Let other divers see the right way to dive.

If you see your dive leader being careless with the reef or the sea life, don’t be afraid to speak up about it. If you see fellow divers exercising little awareness above and/or below the water feel free to give them a few hints. The more we speak up and call out unacceptable behavior, the more we can contribute to preserving these awe-inspiring eco-systems.

Perfect Your Buoyancy with Banyan Tree Divers!

If you are interested in perfecting your neural buoyancy control then we invite you to join us for our Peak Performance Buoyancy Specialty workshop. We will work with you to achieve complete weightlessness like a pro. This Specialty is conducted over two dives and counts toward the completion of your recreational PADI Master Diver certification. Contact BTD for more information!

Happy Diving and remember LUNGS AND LEGS! Aloha

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