If you truely want to understand the way your gases make their way into the tanks this course is a very cool non-diving extra. You will learn how to do calculations so you end up with the correct mix.
After completing this course you will be certified to blend Nitrox and/or Trimix. You will also learn what to look out for while blending and different methods.

You will first learn all the theory behind different blending methods with all their advantages and disadvantages and after that you will actually get to blend gases!