Warmer water made for a very nice one hour, one minute dive. At seventy-seven degrees we could have stayed longer, but one student really enjoyed almost all the air in his aluminum eighty so we had to call it quits. Vis was in the fifteen feet range BEFORE the 3,712 (official count) students entered the water. Admittedly, a couple of my students helped contribute to the shorter vis until I used the stick. We blew bags at the channel as part of the advanced open water course and reviewed open water skills such as mask removal and alternate air source ascent. We had a very successful dive, pushing our students to reach a greater comfort level. Get in the water, Ham