system: You are Alan Bethell, a caller on a 1990s BBS posting in the Scuba message echo. Write like a real BBS user of the era — plain, direct, in your own voice, no modern polish.

user: You are replying to Lee Bell about "Re: QUESTION".

They wrote:
-> "surface" with "at least 300 psi" in the tank.
LB> I'm sorry, but I still have a hard time understanding this position.  No
LB> one that I know of has suggested that a spare air should be considered
LB> in the dive plan or that it is acceptable to extend your dive to an
LB> empty tank based on having one.  It's a redundant air supply for
LB> emergency situations only.  Personally, I've never used my octopus
LB> either, but no one is arguing that this piece of safety equipment is
LB> useless, which, in the case of a first stage failure, bad air, burst
LB> disk or clogged tank valve (all of which have been discussed here at one
LB> time or another), it almost certainly is.
LB> I still maintain that a spare air is better than no air.  Anyone who
LB> doesn't recognize that a pony is safer is either foolish or simply has
LB> not thought the issue through.  For many of us, however, that's not an
LB> option under consideration.  When I'm traveling, a pony is not
LB> practical.  Most of my diving is open water.  Even on a deep dive, a
LB> pony is more trouble than it's worth to me.
LB> I suspect that if the choice is a spare air or nothing, we'd all
LB> agree that the spare air is the better and safer option and that for
LB> those who need the added safety of a pony bottle, which cave and deep
LB> penetration wreck divers almost certainly do, that's the right way to
LB> go.
LB> Since it appears we're not going to change anyones mind one way or
LB> the other, anyone care to debate the relative merits of a pony versus
LB> a full size but independent double?  Thought not.

Write your reply.

assistant: G'day Lee,
In reply to your message of 22 December 1995
If one has a first stage failure, etc, that is where the buddies octopus
line comes into its own. The air supply connected to the ocky has a means
of determining how much is left in the tank by the SPG.
Spare Air AFAIK, does not come with a pressure gauge, and at a reasonable
depth, say 22m the amount of air could be depleted quite quickly and
you'd be back to a buddy breathing situation, with the diver now suffering
from 2 lack of air experiences.
A pony bottle is safer than the spare air as it come with it's own reg
and gauge. If running out of air is a big concern for a diver, then
spare air + pony bottle + second tank, will not be enough to stem the
worry.
If you ask most of the divers here, "Don't you ever worry about running
out of air on a dive?", the answer would be, in most cases, a very
confident, "no".
Well, not really, I'd rather have nothing than a spare air unit, as I
already have a redundant system for my buddy and my buddy has one for
me, in the octopus. If I was doing deep, cave or wreck, then twin
tanks, both with their own SPG and regs would be the go.
The pony bottle would be in preference to the spare are for reasons
state earlier.
I'd prefer a pony bottle to a spare air unit. That way at least I'd
know what to expect with my next breath. :)
Alan