As a group of people we dove around wreckage form an old lumber mill. We didn't find much but I did get a solid look at some well worn boards. My mind started thinking signs, arts and crafts. Perhaps a little graphic painting may do wonders. Ok...sorry I was sort of just talking and talking as my artistic side kicked in.
We did practice some emergency ascents. This is the last of the last of the last resort when someone is out of air. There are dangers if you are deep enough of getting the bends. At 20 feet it won't hurt you but at deeper levels you could have a problem. Make a humming sound and allow air to move in exhale. Stay under the speed of your bubbles.