OP
Far_X
Contributor
Maybe I screwed up as the dive computer probably didn't count the time when I was surface swimming as it was less than three feet from the surface. I guess I should find a more depth consistent site to dive if I want to measure the SAC. In fact, I think I should quit worrying about the SAC until I see the air used is considerably less for the same dive sites with similar time lengths. As you say, my times are all up and down but there is probably no consistency in my calculations so they cannot be relied upon. Whatever the reason, I am still using too much air and will be practicing all that has been mentioned here over the coming weeks. 
