Do you actually see people diving with pony bottles?

[DustyC]

I carry mine in every dive in order to get more comfortable with it for the tech class I'm in. Not just it being there, but to practice gas switching as well. Just like despite almost a thousand dives, i still switch between secondaries and mask switching on most dives.

I dive solo, so it helps there as well. I see very few on cattle boats. I have a friend that always dives one, as he's also a solo diver. But we're the only two at home, that i see.

 

[Dan]

I see what you mean. So the hose length doesn't matter but the decrease in ambient pressure does matter. The volume of air in the hose would only matter if the 1st stage stopped delivering air, and in that case the volume is low enough to not matter. Do I understand you? Thanks.

Assuming the ID of the 7' hose is 0.25", a quick back of the envelope calculation of the hose volume is about 0.002 cf.

 

[HantsDiver]

When I dive with a pony, I carry it slung. The main reasons are accuracy of regulator identification and access to the valve and SPG. The ease with which it can be detached is a secondary benefit, at least for the kinds of dives I make.

As a side note - why bother with an spg on a pony? If it's an emergency get out of jail free card is it needed? If I were to use a pony I would choose to not have one. I am considering taking off the spg's from my stage regs for similar reasons.

 

[lowviz]

As a side note - why bother with an spg on a pony? If it's an emergency get out of jail free card is it needed? ...//...

There is the camp that ascribes to: 'If you need to go to your pony, it doesn't matter what the gauge says'. True enough when it all comes down. But how about on the day-to-day?

You charge the pony, turn it off, and do your dive. How many times can you do this? Much of diving is about peace of mind about your abilities and all of your gear. I KNOW what is in my pony, simple glance.

"I must not fear.
Fear is the mind-killer.
Fear is the little-death that brings total obliteration.
I will face my fear.
I will permit it to pass over me and through me.
And when it has gone past I will turn the inner eye to see its path.
Where the fear has gone there will be nothing.
Only I will remain."

-no reference required for true solo divers.

 

[boulderjohn]

I see what you mean. So the hose length doesn't matter but the decrease in ambient pressure does matter. The volume of air in the hose would only matter if the 1st stage stopped delivering air, and in that case the volume is low enough to not matter. Do I understand you? Thanks.

The first stage delivers air at a certain level MORE than ambient pressure. It depends upon the the make of the regulator, but it is generally about 140 PSI more than ambient. It is adjusted to depth by allowing the ambient water pressure to assist the mechanism that allows for the air flow. As the tank pressure gets close to that level (and beyond), you have to inhale harder to get the air you want, with the pressure of your inhale compensating for the lack of pressure in the tank. That gives you a warning. Your tank is not out of air--it just does not have enough pressure to overcome the ambient pressure of the water around you. You will not be able to pull any air from the tank. As you ascend, the water pressure around you decreases. At some point, the pressure of the air remaining in the tank will be sufficient to overcome the water pressure around you, and you will get another breath. This will continue as you ascend.

 

[CuzzA]

As a side note - why bother with an spg on a pony? If it's an emergency get out of jail free card is it needed? If I were to use a pony I would choose to not have one. I am considering taking off the spg's from my stage regs for similar reasons.

Well, for me personally, I find the SPG important. I use a button gauge, but its purpose is to inform me if the pony has lost any gas. For repetitive dives this is a high possibility from brief surface freeflows/purges when splashing or even sometimes a slight release of gas when swimming against a current. It also allows me to whip my pony full again and not over/under fill the cylinder.

 

[vam]

Thanks for the clear explanation @boulderjohn - much appreciated, and it makes loads of sense.

 

[rek_diver]

As a side note - why bother with an spg on a pony?

Um, so you know that there's gas in there in the event you need it?

It's like saying "I've got these old umbrellas sitting in the attic for the last 20 years, they might be moldy, ripped, torn, full of holes and useless but I won't bother checking I'll just use them when there's a thunderstorm and hope for the best".

 

[The Chairman]

Pony or stage?

If you're using your pony as part of your gas calculations, it's more of a stage in my thinking. Most recreational divers don't have the experience, savvy, training or the mentality to do this safely. Someone called a pony a "Get out of jail, FREE" card for the clueless, and that's a good way to look at it. When I carried a pony (AL20) on my HP120, it was there only to be used in case of an OOA. I dove it for 6 years with the original VIP and Hydro, because I never had the need to use it or refill it. When I sold it, it still had 2600 psi in it. A couple of things I did wrong with that pony setup.

• It was attached behind me
  • It had to be completely on the entire dive
    • A slight free flow could have emptied it without me knowing
    • Charging the reg and turning it off is the only way I carry additional gas now
  • I wasn't able to run my hand along the hose all the way back to it's source
    • "I'm pretty sure this is the right hose" is not near sure enough
    • I need to see the mix/mod before I breathe off of a cylinder
  • It presents another entanglement hazard you can't easily reach
• I filled it with NitrOx 32
  • Ponies should be only filled with air so you don't have to worry about its MOD
• I couldn't remove it during a dive
  • Not able to pass it off to an OOA buddy
  • Especially important if entangled

If you want to use it as a stage, anything less than an AL40 is a waste of effort. Take an Extended Range class and learn how to manage different mixes safely. Chances are, you're going into deco with the extra gas, so you'll learn the gas planning needed for that in the ER class.

 

[JohnN]

Not because of the pony bottle, but because they report Elvis sightings

Thank You Very Much GIF - Elvispresley Kingofpop - Discover & Share GIFs