For those who say these "downcurrents" don't exist or that you can't get PUSHED down to 300 ft...... They are real as I've been in one. One of my early trips to Coz, maybe 96 or 98, around that time. Not sure but think we were on Santa Rosa Wall. We were diving with Dive Paradise, one of their advanced dives. We had entered the water, swam down to the wall edge and began a horizontal sweep across the wall face, maybe 60 or 70 ft. The next thing I noticed was the depth readout on my computer changing constantly, the numbers getting bigger, I wasn't sure but by the time I reacted I had changed 40 or 50 ft in depth. I began adding air to my BC while staring at my computer. My descent continued, I kept adding air. I tried to be calm and added only short bursts of air, I didn't want to overcompensate. Finally my descent slowed and stopped. I had reached 202 ft. I then began to rise and started dumping air. I managed a controlled ascent and found my buddy hovering above me somewhere around 60 or 70 ft. I didn't know what had happened at the time and didn't know anything about "downcurrents". I only realized several years later from posts on this board what it really was.