:) Fun question : How deep have you gone on single tank ? What's your record ?

[AfterDark]

What the diving world needs is another superhero. Those rare individuals with self proclaimed super physiology. They can dive to 200 ft an an 80 filled with air, and have no effects, and surface with 1500psi. Their physiology is such that they don't produce carbon dioxide. This often translates into self proclaimed success at several endurance events, and of course with all this exceptional physiology comes an inherant belief that they are invincible, know everything and everyone else on the planet is inferior. They sprout forth as experts on all topics and their opinions are, of course, the only valid ones, and beyond any challenge from lesser mortals.
Seriously, I have been encouraged by the humility of the posters, so far, on this topic. I think this kind of discussion, while not intentioned to do so, will encourage some people to go deep just for the sake of it and not for a specific purpose.

You could be right. Sometimes all it takes is the opportunity. At the invincible age of 18 I went to 170fsw with a 72cuft no SPG, PDC, or auto inflatable bc, (because they weren't invented yet or way to expensive for me at the time) ,alone just because I was diving some place where it could be done, and nobody else would go with me. I remember when I brought the tank to be filled there wasn’t much air left.

 

[nomro]

42 meters , around 138 feet for me

 

[tstocum]

85 ft on an AL80 in a dark cold quarry. As a general rule of thumb I don't dive deeper than the size of my tank. I think this was something a more experienced diver once told me and it just stuck. Can't remember the reason behind it though.

 

[TSandM]

tstocum, it's a good rule of thumb, and has to do with what some of us call "rock bottom" reserves. That is, if you calculate the amount of gas it will take to get you AND your buddy up from your maximum depth, you will find that that amount for deeper dives (which is always calculated generously, as if you are having to get an OOG diver up, both of you are going to be a bit stressed) comprises a large proportion of the gas supply in smaller tanks. RB from 130 feet, even using the PADI ascent profile, will be about half of an Al80 . . .

 

[joe8mofo]

If you have a pony bottle with you does it count as single tank?

 

[elan]

If you have a pony bottle with you does it count as single tank?

If you left it in the stable

 

[Splitlip]

When I was a relatively new diver (about 80 dives) I went to 137 feet on an AL80 ... and air. It's not something I'd ever contemplate doing today, but back then I didn't know any better ... despite my belief (back then) that I knew it all ...

... Bob (Grateful Diver)

Funny...when you're a kid, you think any thing goes. "live fast, die young, leave a good looking corpse" and all that. Then the older you get, the more precious life becomes.

oh..147' on air in a steel LP 72. My AOW deep dive. it was an accident. we missed the barge.

 

[joe8mofo]

If you left it in the stable

I guess then the answer I have to post is "I have not exceeded my training with a single tank" so 127 FFW

 

[Tortuga68]

tstocum, it's a good rule of thumb... RB from 130 feet, even using the PADI ascent profile, will be about half of an Al80 . . .

How is 'don't dive deeper than the size of your tank' a good rule of thumb if it's out by >60%

 

[D_B]

Until you have or are experienced , the "don't dive deeper than your tanK" is a good rule of thumb

Another rule of thumb for recreational depths for PSI time to start up / reserve air (rock bottom) that I use is from Lamont's useful post on it ... for my HP100 tank it would be - Depth , add a 0 to it , + 400 psi ... IE at 100ft +0 +400 = 1400psi to start ascent ... an AL80 would be +500psi

and I think we should not post in Basic Scuba about a depth you have dived on a single tank without mentioning your experience level
... 109ft witha 100cf tank on the wreck Baja California , with AOW and Rescue , and several dives to 90 - 100