Pony vs. H-Valve

[Lemonade]

Why carry a pony tank if you can get an H(Y)-Valve?

Here are my thoughts:

• H-Valve is less expensive than a pony bottle + harness.
• Both provide same redundancy for the first stage.
• More air with pony? Why not get a larger tank? Seems like 120 cf + H-Valve is a less cumbersome setup than a 100 cf + 20 cf pony.

Am I missing something?

I’d like to hear what you guys think, and what other considerations are out there.

Thanks.

 

[DiveTub]

Here are a few reasons I carry a pony

You can't put a different gas mix in an H Valve

You can't give an HValve to another diver in a OOA emergency, a pony you can just hand to them, much easier than breathing off one bottle.

You can't clip an H Valve onto the deco line

A Pony is always full of Air, an HValve only has what is left in your main tank.

I dont even notice my pony slung under my arm

Cheers
Chris

 

[MikeS]

H-Valve is less expensive than a pony bottle + harness.

I do not believe that this is necessarily the case if you have multiple tanks. In both cases you need a second regulator so that is a wash. If you have two tanks, you need two H-valves, three tanks three H-valves, etc, versus the cost of a single tank and $10 worth of rope and snaps to stage sling it.

Both provide same redundancy for the first stage.

True but a pony also provides a redundant tank and a valve.

More air with pony? Why not get a larger tank? Seems like 120 cf + H-Valve is a less cumbersome setup than a 100 cf + 20 cf pony.

For me the idea is not to have more air, it’s to have a totally independent SCUBA. I carry it only for use in getting to the surface in the event of a failure of the primary system, it has never been used other than for practice and I hope it never will.

A stage slung pony is not cumbersome once you’re in the water.

Am I missing something?

I like having the valve where I can see it. While I suppose it is possible with the correct training to deal with an H-valve I do not want the increased task loading in an emergency.

An H-valve is also not a good option if you are renting tanks because of travel, nowhere that I know of rents tanks with H-valves. I can take the valve off the pony and take it with me on the plane.

You can hand off the pony to an OOA diver that is not your buddy and still have your octo as your buddies backup.

Mike

 

[Spectre]

Lemonade once bubbled...
Why carry a pony tank if you can get an H(Y)-Valve?

• Pony gives redundancy on the regulator, and redundancy on the air supply.
• No matter how narced you are, you'll never calculate your pony air supply as usable
• It can be handed off
• It can have different gas
• The amount of reserve gas you have is not proportional to how fast you can get to a knob.

 

[JimC]

You can't put a different gas mix in an H Valve

Thats not a pony bottle, its using your pony as a deco bottle. No one is going to argue the benifits of using diferent gas to deco.

You can't give an HValve to another diver in a OOA emergency, a pony you can just hand to them, much easier than breathing off one bottle.

True. But this should idealy never happen. You already have a reserve and if you are planing your dives corectly the backup will have enough gas. Making an OOA easier (how often does this REALY happen?) trade off for the extra task loading and complexity of carrying it. Thats a valid arguable point.

You can't clip an H Valve onto the deco line

Deco bottles are no pony bottles. If your using your pony for deco, well.. its not a pony is it?

A Pony is always full of Air, an HValve only has what is left in your main tank.

Which should never be less than enough to surface you and your buddy.. right?


What a pony adds over an h-valve solution:

Redundant neck o-ring.
Redundant tank.
Handoffable (asuming you don't have the thing stuck to your tank).
3rd second stage.
You can recycle your pony into something more usefull.. like a deco bottle.. unless you got suckered into buying a tiny one.


I have never heard of a neck seal going.
I have never heard of a tank failing under water.
You already have a backup 2nd stage.

So you get handofability in the event its usefull. Which should idealy never happen, and in practice happen rarily, and only in the event of equipment failure, which is mostly avoidable. Almost all of which are solved with an h-valve.

And if you move to more demanding dives you might get to reuse your investment. Me, if/when I need a deco bottle, I will buy the right one specificaly for that reason.

 

[Rick Murchison]

pony n., 1. small horse 2. something small of its kind (Webster's)
"Pony" refers to a small compressed gas cylinder, not its use. A pony used as a deco bottle is still a pony. They can also be used as "backups"... Down here, a pony used as a redundant gas supply is called a "bailout bottle." But "pony" just means "small."
------------------------------------
As far as "H" valves and pony bottle comparisons, all the advantages to using a pony have already been covered in prior posts - what hasn't been mentioned is the chief advantage of the "H" valve, which is continued access to your entire gas supply in the event of a regulator failure. Just shut off the bad reg and you still have it all.
Which way do you want it? Each has its advantages. Or, you can use both... On many deco dives I carry my deco gas in a pony and use an "H" valve on my back gas if I'm not wearing doubles.
Rick

 

[Spectre]

JimC once bubbled...

Thats not a pony bottle, its using your pony as a deco bottle. No one is going to argue the benifits of using diferent gas to deco.

Not necessarily. EAN32 in the tanks, air in the pony is definately _not_ a deco bottle... it's a bailout bottle.

 

[redacted]

I do about half my diving on trips involving air travel. The destinations always have Al 80s with K-valves readily available. In many places, getting anything other than that is not impossible but a PITA with extra cost. The pony travels easily and does the job.

 

[Lemonade]

You can recycle your pony into something more usefull.. like a deco bottle.. unless you got suckered into buying a tiny one.

What is the minimal size that is generally considered sufficient for a pony bottle? 13+? 19+? 30+?

Thanks.

 

[Rick Murchison]

Lemonade once bubbled...



What is the minimal size that is generally considered sufficient for a pony bottle? 13+? 19+? 30+?

Thanks.

That depends on what you're using the pony for. If all you want is a bailout bottle for your typical NDL recreational dive, 13CF is, to me, the minimum. I usually use a pony as a deco bottle where my deco gas requirement is around 15 CF, so I use a 30. I understand 40's are popular up East.
Rick