He seemed to have a very real need of oxygen.

Lower the amount of oxygen available to you and your growing baby.

His face had turned blue from the lack of oxygen.

Lack of oxygen was making him begin to black out.

Children don't have long before they turn blue from lack of oxygen.

It is given to increase the amount of oxygen in the blood to provide for the body's needs.

Second, is the amount of oxygen that's actually in the water.

Nearly 80% of the oxygen used by the fish is taken in this way.

So if you increase the amount of oxygen present, what happens then?

This process must be done in the presence of oxygen.