I recently received an oxygen kit as a gift, and I"ve used it on my last couple batches. I've noticed that I have a much longer lag time than I did when simply shook the bejesus out of my carboys. I even more recently brewed with a friend (and I administered the oxygen) and he said he noticed an abnormally long long on his end too. I know it's not the yeast, as I'm a microbiologist and have been growing up yeast well for a long time. Furthermore, they were foaming heavily in the starter and VERY active. The only thing different in my process is the oxygen. This was a moderate gravity beer OG: 1058. What I have been doing is
I put the wand into the beer and turn on the O2 until I see bubbles forming and rising. I move it around, but kept it submerged for 75 seconds (originally was 60, but wanted to see if more oxygen helped). Am I missing something?

