Carlos' stage bottles were all similar looking. Some marked with a 70, the rest marked as oxygen 20. Before his Doria trip, all of them were filled with 50% and 100% respective to the permanent markings on the bottles. They were then analyzed and marked with duct tape as that was the routine. The duct tape labels were always removed before filling and new ones made at analysis time.
He went on the Doria trip a few weeks ago. Conditions were rough, so the group didn't get all of the planned dives in. He brought home some full bottles and some not full bottles.
That much i can say with certainty. What I assume happened next is that he filled one or more of the low bottles with air, brought it home and placed it with the full o2 bottles. When packing to go to Florida, must have grabbed the wrong tank.
That is how I have pieced it together in my head. I could be wrong about the last part, but my guess is that there is an air bottle in his garage.
Carlos was a very close friend of mine. I met him 4 years ago, while on a charter in Tobermory. We got along immediately and have gone on many great adventures since then.
When I got news of the tragedy, i was shocked. The Carlos I know always checked and double checked his mixes. I would know, because i was usually with him while mixing. I am at a loss as to how he let this happen.
One way or another, Carlos was a kind, generous person who would drop everything to help anyone who ever asked. He was a huge promoter of the sport and always encouraged newer divers, without ever being judgemental.
To call someone an idiot is harsh and disrespectful. Family and friends often find their way into these threads. The last thing they need to see is the mud slinging that is going on. He made a mistake and paid with his life. He doesn't need to pay with his dignity.
I will always miss you and remember the good times.