7 Diving Buoyancy Facts That You Need To Know
1. Proper weighting – You need to weigh yourself to be neutrally buoyant with an empty BCD and at gas reserve level (50bar/500psi) at safety stop depth. The ‘float at nose level type of weight checks and calculations taught in most mainstream entry-level or diving buoyancy speciality courses are very flawed; typically leaving you grossly over-weighted. Being over-weighted exacerbates your struggle to achieve and maintain neutral buoyancy.

2. Consistent horizontal trim – You need to stay in trim – otherwise you’ll be unconsciously compensating for negative diving buoyancy as you fin; i.e. if you’re pushing water downwards and not moving upwards in the water… then you’re wasting energy (and gas!) by propelling to hold a constant depth. That isn’t buoyancy control – it means you’re negatively buoyant and you’ll begin to sink whenever you stop finning.
3. Frog kick – Develop more refined propulsion techniques. This is another means to ensure that you aren’t unconsciously compensating for negative diving buoyancy as you fin. Frog kick, done properly and in trim, doesn’t direct water downwards – so it can’t compensate for negative diving buoyancy.
4. Static Practice – You have to be motionless to isolate diving buoyancy control. If you are finning along or sculling then you’ll instinctively and unconsciously compensate for a lack of neutral buoyancy using your fins. This is why “diving buoyancy training” by swimming through hoops etc is worse than useless – it gives only a deceptive illusion of diving buoyancy control and actually promotes divers to compensate for bad diving buoyancy using propulsion. Training shouldn’t instil such counter-productive habits – and yet far too many lacklustre instructors still do exactly this.

5. Breath control – There are some very effective and efficient drills which teach this in literally minutes. Sadly, very very few instructors know or utilize those drills.
6. Dedicated practice with immediate feedback and correction. Simply going diving is very inefficient in developing proficiency improvement. Schedule specific practice sessions with an expert instructor/mentor. Not all instructors are even close to a level of expertise in fundamental skills.
7. Practice time – While you can consciously learn a new skill within minutes, it takes hours of repetition over days of practice to ingrain that skill as an unconscious or autonomic function. If a skill isn’t unconscious, then it is unreliable under stress and will also impede your situational awareness (and enjoyment of diving) by demanding your constant attention. Far too few courses/instructors allocate adequate time for students to develop their fundamental skills to an appropriate level of unconscious fluency.
About the Author
Andy Davis is a RAID, PADI TecRec, ANDI, BSAC and SSI-qualified independent technical diving instructor who specializes in teaching sidemount, trimix and advanced wreck diving courses.
Currently residing in Subic Bay, Philippines; he has amassed more than 10,000 open circuit and CCR dives over 27 years of diving across the globe.
He has published numerous diving magazine articles, designed courses for dive training agencies and tests/reviews dive gear for scuba equipment manufacturers. He is currently writing a series of advanced diving books and creating a range of tech diving clothing and accessories.
Prior to becoming a professional technical diving educator in 2006, Andy was a commissioned officer in the Royal Air Force and has served in Iraq, Afghanistan, Belize and Cyprus.