I took advantage of a business trip to Denver in January by flying there early and spending the weekend diving. Diver’s Reef in Colorado Springs was diving in Santa Rosa the weekend of 26-27 January. I was looking to work on buoyancy skills and get some certs (Peak Perf Buoyancy, Multilevel/Computer, Altitude). They gave me a great deal – providing air, weights, a ride in their van to & from NM, plus the instruction for $200. I arrived at the dive shop on Friday after lunch and hung around until we left. I helped load their van w/ tanks and gear. We were on the road around 4pm. Saturday, I learned more about diving at altitude. Different ways to account for altitude. Also, since air density can change, it was interesting that my dive computer had us about 2k feet higher than we were (7k feet instead of the 5k reading I should have at 4600 ft). So, in that sense, the computer was definitely a plus that accounts for weather changes at altitude. While there is a table that does the calculation for effective depth at different altitudes, some folks will simply add 10 or 15 feet to their planned depth (if diving tables as a backup) to account for altitude. I worked on my buoyancy all weekend. I got to the point where I could control my depth within about a ten foot range simply by my breathing. I thought that was really neat. I also worked on my weighting and where I wore my weight. Since I’ve been back to sea level, I wear two pounds less than I wore at Blue Hole due to less expansion of the air in the neoprene of my wetsuit. While I read about that type of difference, it was also cool to witness the difference. Sunday, I dived the multilevel using the Wheel. Personally, I like the wheel better than the standard RDP. But, it is a hassle to do altitude adjustments. My first dive was a three level dive. Each change of level required two adjustments (one on each side of the Wheel). That being said, I still prefer the Wheel because it has more depth selections and has less rounding errors (granted, the rounding on the RDP errs on the side of safety). The bottom of the Blue Hole was neat. Since I was the first one in on Sunday, visibility was awesome. I took a light, because the sun was still close to the horizon (about 8am). Saw a few crawfish. I also thought it was neat when you are under one of the overhangs how the bubbles look like mercury. You can move them around with your fingers. Pretty neat.