pony bottle-open or closed?

[Emparo821]

I have never used a pony, but was curious. if it is mounted on your back then do you run the extra reg to the front like an backup reg or do you keep the reg stuck to the pony like a stage or deco bottle?

i ask cause it would make sense to open it up once your under if its attached to the front like a backup but if you have to pull it out i would think that it would safer to just train to open the valve as your pulling it out.

*edit: but from what i've picked up evad's answer sounds like the best option to me, and to answer the post after this one, i would say that you communicate with any dive buddy bbefore the dive as to how you have the pony setup so that he knows to turn it on if he needs it, then you both know to turn it on after it breaths hard on the first breath

 

[Wookie]

open.

 

[knotical]

Open, in case a distressed diver grabs my alternate.

Your answer might depend on who you dive with.

I often dive with novices and students, so I want to appear as "standard" as I can.
The majority are familiar with a recreational configuration of a bright-colored alternate second stage hanging near my lower right ribs, and that's what they see. From the front, the only way anyone would know that I'm carrying a pony is that I have a second spg (which I also monitor). From the back you can see the extra tank, extra first stage, and extra spg hose.

 

[Druid]

Open

1. The OP is using a yoke valve. It's the pressure in the cylinder that forms the seal, so it's less likely to leak if it's on

2. The pony is there for when the **** hits the fan. In that situation you want your emergency gas to be immediately available, you don't want to have to look for a valve and open it before you get your next breath.

 

[Splitlip]

I charge the reg on the surface then close the valve.

 

[Randy g]

I sling and its charged before entering then closed until it is needed. I normally open the valve while diving just in case, but thus far it has always held a charge.

 

[divad]

Open, in case a distressed diver grabs my alternate.

Your answer might depend on who you dive with.

I often dive with novices and students, so I want to appear as "standard" as I can.
The majority are familiar with a recreational configuration of a bright-colored alternate second stage hanging near my lower right ribs, and that's what they see. From the front, the only way anyone would know that I'm carrying a pony is that I have a second spg (which I also monitor). From the back you can see the extra tank, extra first stage, and extra spg hose.

I had presumed the OP was only using the pony when solo diving.

 

[Splitlip]

same. That's when I use one.

 

[divad]

same. That's when I use one.

And if your buddy(s) can't tell the difference between a slung pony with a DIN valve and your regulator-to-be-donated, then you are better off solo diving or not diving.

 

[randy88k5]

I sling my pony, and keep the regulator charged (turn on and off and do not purge). I charge at the surface, after entry as I go down, and again on the bottom. I usually notice a pressure drop of about 1000 psi in the charged system between the surface and the bottom. So, if you keep it open, there is a good chance you are losing a little bit of gas.