Best type of Pony Tank setup?

[Zac3G]

I'm just wondering if anyone has an opinion on witch Pony Tank setup is best. There is the style without a hose like the H2Odyssey that goes on your BC, or the type that goes on your tank with a hose and octo. type regulator. I can see pluses and minuses for both. I'm getting ready to buy one and would like to hear any input you may have... Thanks...

 

[Uncle Pug]

I'm getting ready to buy one and would like to hear any input you may have... Thanks...

Well I would say that it is best not to carry a pony in the first place. If you must carry a pony because you cannot figure out how to plan your gas needs and leave an adequate reserve then I would say don't mount it on your back where you can't get to it.

Here is an example of a front mounted 40cf bottle.

 

[Uncle Pug]

Here is the bottle from the front showing the rigging. This is a picture of my EAN50 deco bottle but you could rig a smaller pony the same way. It can be detached and handed off to an OOA diver. The bottle is turned on to charge the reg and then turned back off. The SPG is on a short 6" hose bent back and tied off to the reg. The second stage is on a 40" hose and is held to the bottle with large rubber bands.

 

[IndigoBlue]

Well I would say that it is best not to carry a pony in the first place. If you must carry a pony because you cannot figure out how to plan your gas needs and leave an adequate reserve then I would say don't mount it on your back where you can't get to it.

Here is an example of a front mounted 40cf bottle.

Zac3G, if you take a look at some of your friends who dive with their own alternate air sources, you may see three choices. UnclePug mentioned the technical mounting. That is the one I favor as well.

There is also tank mounting, which you will probably see often, but which I do not recommend.

Third, there is the option of the small spare air cans that you mentioned in your post. I almost never see anyone using those. And I do not recommend them myself.

The scuba literature in the training manuals exhibit alternate air sources as a valid means of having redundancy in your air supply. As a safety measure, if it works and if it is reliable, then it enhances your safety. Only the type of mounting that Uncle Pug has illustrated is completely reliable. The others have major potential flaws, in my opinion. Even so, you will see many divers using each of them. Take a look at what others around you are diving with, then make your own choice.

 

[DA Aquamaster]

A Spare air is about as large an object as you can manage holdong with just the mouthpiece. Anything larger will require a hand dedicated to holding it and that is not a good idea. That pretty much rules out the larger ponies with the attached hoseless second stages. Also in my opinion a spare air is not an option as a spare air is too small to be truely useful in a true emergency if you are in anyway delayed form immediately ascending. In my opinion the extra confidnece it inspires can be a dangerous thing.

I would recommend a conventional pony bottle of 19 to 30 cu ft. with a conventional regulator. You want enough air to safely and normally finish the dive and any required deco or safety stops from any point in the dive and at least 19 cu ft would be required to do that from any significant depth.

Mounting the pony as a stage bottle is the tech approved way to do it and offers the ability to turn it off and on and the ability to hand it off to another diver. I think it works great in technical situations but is not always a great idea for the average recreational diver.

Handing a slung pony off to a semi panicky recreational buddy who has no clear idea how to stow it when he has it is not a real good idea and can just compiund his problems in an already demanding situation.

Tank mounting a pony allows it to be used in a pretty much invisible manner where it functions like a conventional octo as far as you and you buddy are concerned but with the benefit of a redundant airsource. I have never had a problem with air loss from a properly tuned pony reg I do not see a significant disadvantage to not being able to readily access the valve to turn it off in normal recreational use.

Another advantage of a tank mounted pony is that it is not attached to the front of you and does not get in the way at any point during the dive. It also requires no additional traning to use efficiently, and that is not entirely true for a slung pony bottle.

However you mount it, you shoudl not count on the gas being available. Its sole function is to act as a redundant air source in the event that you suffer a failure of your primary regulator or air supply.

In short I agree with Indigoblue that you should base your decision in large part on who you dive with. If they are technically oriented and trained, sling it. If they are rec divers, back mount it.

 

[Doc Intrepid]

While I often agree with DA Aquamaster, in this case our opinions differ.

For Recreational divers, IMHO it is always best to have both primary and secondary (octopus) second stages attached to the first stage of the diver's backgas regulator. Should some OOA situation occur, this allows both team members access to the backgas.

If you agree, then when you mount your pony bottle attached to the single tank on your back, you now have a third second stage coming over your right shoulder (from the pony bottle regulator).

How do you stow this third 2nd stage so that it doesn't dangle but is readily available?

If you disagree, and indeed treat your pony regulator second stage as your octopus, then you only have one second stage off your backgas regulator. Your "octopus" ostensibly comes off your pony. In the event of an OOA situation, both divers do not have access to the backgas (unless you begin buddy-breathing, which is nowadays considered unwise).

Pony's offer few benefits that outweigh their liabilities from the start.

But to add weight, cost, complexity, and then have your convoluted setup also provide a third 2nd stage from an gas source you can neither access the valve for, unsling or reach to untangle if fouled, nor track consumption of, seems a bit unnecessary.

If you intend to carry a pony, sling it and train regularly with your buddy on how to use it. IMO, backmounting a pony is the point where the liabilities outweigh the benefits.

Just an opinion.

Doc

 

[TechBlue]

I agree with uncle Pug and the Doc, Pony bottles are a convoluted method of carrying a redundant gas supply which was started here in the NE. As far as a panicked recreational diver goes, watch out, the reg they are going to go for will be the one in your mouth. The disadvantages of a Pony bottle are, you can't reach the valve to either turn it on or off, and it can be the source for a major line entanglement which again you can't reach. Because of the position they also tend to keep you off balance in the water.
Slinging a stage is a cleaner approach I think most of which has been covered already and depending on your dive entry and exits you can clip the stage on just before you hit the water and hand it off before you get out.

Chris

 

[DA Aquamaster]

Good point Doc, I should have added that I am also a fan of the Air 2 type of alternate second stage.

When I used a pony, much of my diving was solo and the pony was needed to replace the redundant air carried by the absent buddy. I found an Air 2 to be ideal for this situation as it allowed a backup second stage on the primary tank and avoids a third hose and conventional second stage that would otherwise be present with a tank mounted pony.

In an OOA air situation with a buddy I believe in donating the primary which then leaves you the option of using the Air 2 as an octo or breathing off the pony bottle. (And whether you ascribe to the donate the primary theory or not, in my experience, the odds are you will be donating the primary as most of the time the out of air diver will take it right out of your mouth with none of the air share ettiquette that occurs in training.)

Most of my diving (90+%) is in cold water. The last OOA situation I was involved in with a pony was in 40 degree water, at 100', with a huffing and puffing buddy on the primary. I opted to breathe off the pony to avoid additional cooling stress on the primary first stage. I figured the last thing I needed at that point was another frozen first stage. We were aborting the dive and heading directly to the surface (which should be the case in any rec dive where air sharing is required) so there was no downside to using the pony.

In an overhead situation, the need to use backgas is more likely to be the case in order to either exit a wreck or return to an ascent line and then ascend to the first deco stop. Breathing off a pony makes no sense in this situation, and a long hose primary is really nice to have along. But then in an overhead environment even having a pony bottle along as anything other than a slung deco bottle makes no sense at all so the issue should never come up.

 

[Druid]

I'm a recreational diver and most of my dives are to less than 30m (100 ft). I use a 3ltr pony as my redundant air supply, it's not for sharing. If my buddy needs air, (s)he can use my octo (or more likely my primary, as deepbluetech points out).

So, I have a normal primary and octo on my main tank, primary coming over my right shoulder, octo over my left shoulder and clipped to a D ring on my BC. The pony is mounted inverted on the right hand side of the tank, with the regulator secured using a couple of rubber bands as shown in Uncle Pug's pic. The valve is easy to access, and so is the regulator. Regular practice means that I know exactly where the reg is; drop my right arm to my side, grab the reg and pull it free.

Though I've never had to use it for real, it works for me.

While we're on the subject, I still don't understand the dislike some divers have for pony cylinders. Sure they don't hold enough gas to do a deco stop ascent from 45m, but that's nor what they're for. I never plan to use the gas in the pony, it's there just in case. They're lighter, cheaper and easier to manage than twins, and are a perfectly acceptable piece of kit for a recreational diver to use, IMO.

 

[Dive Source]

Have to agree with the practice of sling mounting the pony . It's easy to do and can even be handed off in an emergency.

On a side note

Also in my opinion a spare air is not an option as a spare air is too small to be truely useful in a true emergency if you are in anyway delayed form immediately ascending. In my opinion the extra confidnece it inspires can be a dangerous thing.

I have to say I used to think they were junk too until I actually took one out in openwater to evaluate it objectively. I managed to reach the surface from 90 ft on a spare air at a standard ascent rate and while they certainly don't allow you time to mess around they can get you up and have a place with travelling divers looking for a backup.

For local diving - Ponies certainly offer more time to work things out...