Negative buoyancy

You sink because you are heavy. Negative buoyancy occurs when your total weight is more than the water you displace. This state is common during the initial descent phase of a dive. You often experience this when you exhale or vent air from your BCD.

In technical diving, some divers use a negative entry method. They sink quickly through the surface layer so that waves do not toss them around. I saw this often in Komodo during 2018 while we faced heavy surface swells. However, recreational divers must avoid uncontrolled sinking. A common mistake is forgetting to check your weight after adding heavy gear like thick 5mm wetsuits. Always test your buoyancy at 5 m before you descend further.