SDI Open Water Scuba Diver Practice Exam 2025 - Free Scuba Diver Practice Questions and Study Guide

When experiencing unstable buoyancy while scuba diving, the most effective response is to adjust your weight and the air in your buoyancy control device (BC). Buoyancy control is essential for maintaining a safe and controlled position in the water column. If you find that you are either positively or negatively buoyant, it may indicate that your current weight setup or the amount of air in your BC needs to be modified.

By adjusting the air in your BC, you can effectively manage your buoyancy. If you are positively buoyant, letting some air out of your BC will help you descend, while adding air will assist you in ascending if you are negatively buoyant. This allows you to achieve neutral buoyancy, where you neither float to the surface nor sink, enabling better control, comfort, and safety underwater.

The other options do not address the underlying issue of buoyancy. Swimming rapidly might increase your risk of using excess air and can cause fatigue without resolving buoyancy problems. Stopping completely and holding your breath can be dangerous, especially if you start to ascend unintentionally. Removing your BC is not practical and would likely worsen the situation by removing your means to adjust buoyancy effectively. Therefore, focusing on adjusting your weight and air in the BC provides the