One of the most persistent scuba diving myths is the idea that you should open your tank valve fully and then turn it back a quarter turn. This practice dates back to older equipment, when tank valves could seize if fully opened.
Modern scuba valves are designed differently. They are meant to be fully open during the dive. Turning the valve back can actually create a dangerous situation where the valve appears open but is only partially allowing airflow.
This often reveals itself during descent, when a diver suddenly feels restricted breathing and assumes a regulator failure — when in reality, the tank valve was never fully open in the first place.
✅ The truth: Open your tank valve fully and leave it there. Then take a few deep breaths while watching your pressure gauge. If the needle doesn’t move, your valve is open and your gas flow is unrestricted.
Another classic dive-deck “ick” is blasting air into the dust cap with the tank valve. It’s loud, startling, and makes everyone nearby flinch.
The intention is usually good — most divers are simply trying to dry the dust cap before sealing it. But forcing high-pressure air into it can do more harm than good, potentially pushing moisture, salt, or fine sand straight into the first stage.
If your dust cap is wet, there’s a much simpler solution. Just gently blow on it with your mouth or dry it with a towel. No noise, no risk, no annoyed dive buddies.
✅ The truth: Blowing the dust cap with your cylinder valve is unnecessary — and one of the most universally disliked scuba diving habits.
Nitrox, or Enriched Air, is surrounded by more myths than almost any other diving topic. A very common belief is that diving Nitrox allows you to go deeper or improves your gas consumption.
In reality, Nitrox limits your maximum depth rather than extending it. Because the oxygen content is higher, the maximum operating depth (MOD) becomes shallower than when diving air. Exceeding that depth increases the risk of oxygen toxicity.
Nitrox also does not improve gas consumption. Your gas usage depends on breathing rate, buoyancy control, trim, and how relaxed you are — not the oxygen percentage in your tank.
Another frequent claim is that Nitrox makes divers feel less tired. While many divers report this subjectively, there is no scientific proof showing that Nitrox directly reduces post-dive fatigue. Any perceived difference is likely due to more conservative dive profiles rather than the gas itself.
✅ The truth: Nitrox does not let you dive deeper, does not make your tank last longer, and does not make you immune to decompression sickness. Its real benefit is reduced nitrogen uptake and extended no-decompression limits on repetitive dives.
Most scuba diving myths started with good intentions. They were often correct at one time, but equipment, materials, and training standards have evolved.
Habits passed from diver to diver tend to stick — especially when they’re repeated without explanation. Over time, myths become “rules,” even when they no longer serve a purpose.
At Bali Dive Resort and Spa Tulamben and Bali Dive Resort Amed, we regularly see these myths carried forward by divers of all experience levels. That’s why our instructors focus on explaining why things are done a certain way, not just how.
Scuba diving is safer and more refined than ever before, but only if divers stay up to date. Refreshing your knowledge, asking questions, and understanding modern best practices helps keep diving relaxed and enjoyable.
If it’s been a while since your last course, a PADI Advanced Open Water or Enriched Air (Nitrox) course is a great way to update your skills and knowledge while diving some of Bali’s best sites.
Because the ocean is full of incredible experiences — not outdated myths.
If some of these scuba diving myths sounded familiar, you’re definitely not alone. Diving practices evolve, and staying up to date makes every dive safer, more relaxed, and more enjoyable.
At Bali Dive Resort and Spa and Bali Dive Resort Amed, our experienced PADI instructors focus on modern training, small groups, and clear explanations — so you understand why things are done, not just how.
Whether you’re interested in fun diving, refreshing your skills, or taking a PADI Advanced Open Water or Enriched Air (Nitrox) course, we’re happy to help you plan dives that match your experience level and goals.
👉 Get in touch with us to plan your next dives in Tulamben or Amed — and leave the myths behind.
For many divers, the legendary Mola Mola (Ocean Sunfish) is one of the main reasons to visit Bali during the cooler months. Traditionally associated with Nusa Penida and its famous cleaning stations, these gentle giants attract scuba divers and underwater ...
