New Jersey Scuba Diving

A "same-source" octopus is an extra second-stage regulator that attaches to the same first stage and air supply as your main regulator. Your own same-source octopus is only useful to your buddy, and then only if you are together. The only same-source octopus that will be of any use to you in an emergency will be your buddy's, not your own, and again, only if you are together. In the tropics, where you can see your buddy 100 ft across the reef and the likelihood of getting separated is slim, this scheme can work very well.

However, in the low visibility conditions of the North Atlantic, counting on your buddy to be there with your emergency backup air supply when you really need it is courting disaster. You can not and should not rely on any air source that is not on your own back.

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