Using a pony bottle?

[jsado]

I really don't know anything about pony bottles. If I dive a single s80 but would like to get some more bottom time, could I use a pony for my ascent?

 

[rcpilot44]

You should never use a pony to extend your bottom time. I dive with a 19. I use it only in emergency. It will bring me up safely. I got tired of running low on air, so I went out and bought 2 130s.

 

[jsado]

So, you should never plan a dive where a 19cf pony is figured into your bottom time? Sorry if these questions are ridiculous, but..... Why can't you?

 

[hudson]

In fact you can use a pony to extend your bottom time, but not in the way that you are picturing. Here's why:

There is a certain amount of reserve gas that you should always maintain to get you and your buddy up from your current depth, which is called "rock-bottom" for short. This is tapped during an OOA situation. Do a search and read about it. You should always have more air than your rock-bottom reserve. Typically, a 19cf or even 30cf pony will not have enough air for you and your buddy during an emergency, therefore you can't breath your main tank down and switch to the pony during the normal course of the dive. You would have too little gas to continue the dive safely.

The pony does end up extending your bottom time however, because now some of your rock-bottom reserve (typically half) will be in the pony bottle so you don't have to reserve as much air in your main tank.

 

[AndrewJD]

So, you should never plan a dive where a 19cf pony is figured into your bottom time? Sorry if these questions are ridiculous, but..... Why can't you?

Well, a Pony Bottle is supposed to be a gas supply, independent from your primary, that is to be used in an emergency situation only. It is is supposed to provide redundancy should you experience a total loss of gas to your primary (i.e., 1st Stage failure). It would typically be sized to provide enough gas to do a normal ascent to the to the surface.

On the other hand, if you want to increase your available gas you need a bigger tank, doubles, or a stage.

Now the confusion comes from a stage being incredibly similar to a pony bottle in set up. The difference is in how the gas in the bottle is used in a dive.

Hope this helps.

Jonathan

 

[8251reefer]

Using a pony bottle to increase any sort of bottom time is a big nono in the diving community. I would say that you could use it to practice actually using a pony during your safety stop to become familiar with deploying it. I would instead invest in a bigger tank like a 100hp or 120hp. I have a 30 cuft pony that I setup as a backup and I hope I never have to use it...

 

[drbill]

I always dive with a pony whether solo (my normal style) or buddied up. The only exception is when I'm traveling internationally or long distances in the States. I never use the pony to extend my body time with one exception. If I'm back in the shallows (above 30 ft) and find something I just HAVE to film, I may use my pony to give me enough time to film it if my primary gas supply falls below 500 psi.

 

[jsado]

Now the confusion comes from a stage being incredibly similar to a pony bottle in set up. The difference is in how the gas in the bottle is used in a dive.

Hope this helps.

Jonathan

I've started doing a little research on stage bottles. As of right now, I have no idea what the difference is. Here is some of the info I've found

"Stage bottles are used to provide additional gas on dives where the back-mounted tanks alone cannot carry a sufficient quantity by themselves."

"deco and stage bottles should be permanently marked with the Maximum Operating Depth (MOD) of the gas they're intended to contain. The single largest cause of death among technical divers today is breathing the wrong gas."

....as far as the MOD stuff goes. I don't get it. And by not getting it, I also realize that I probably don't need it, yet. Looks like I'll just buy a bigger tank and say forget the sling. This almost makes me wish I never bought the gear that I bought. Perhaps I would have been much better off with a backplate and wing as a beginner rig. It can expand with you as your diving capabilities do.....

 

[ScubaSteve]

I've started doing a little research on stage bottles. As of right now, I have no idea what the difference is. Here is some of the info I've found

"Stage bottles are used to provide additional gas on dives where the back-mounted tanks alone cannot carry a sufficient quantity by themselves."

"deco and stage bottles should be permanently marked with the Maximum Operating Depth (MOD) of the gas they're intended to contain. The single largest cause of death among technical divers today is breathing the wrong gas."

....as far as the MOD stuff goes. I don't get it. And by not getting it, I also realize that I probably don't need it, yet. Looks like I'll just buy a bigger tank and say forget the sling. This almost makes me wish I never bought the gear that I bought. Perhaps I would have been much better off with a backplate and wing as a beginner rig. It can expand with you as your diving capabilities do.....

I would personally say you are getting way ahead of yourself. Learn and master what you need to as a new diver and work yourself up to technical diving (which is essentially what you are talking about when going to doubles and stage bottles). Learn to dive more efficiently and your bottom time will naturally increase. Most new divers say they are comfortable underwater, breathe normally etc.....they are then humbled when they see their air last longer because of many factors.

Live, Learn and dive often. Watch 100 dives from now how your air is.

 

[Rick Inman]

You're not looking for a stage or deco bottle. You're not looking for a bail-out bottle.

A stage bottle might be dropped on route during a cave dive to be picked up and used later. This is a technical dive tool requiring advanced gas planning and contingency skills.

A deco bottle is used during decompression stops, also a technical dive tool requiring gas planning and contingency skills.

A bail-out bottle is carried and used to exit a dive in the event of catastrophic gas failure. This is usually carried by recreational divers and rebreather divers.

A person could carry a "pony" bottle with them and breath it at the beginning of the dive to extend bottom time. However, IMHO, this is an improper solution to a non-problem. To increase bottom time, gain experience and increase breathing efficiency, and/or increase tank capacity. Most experienced divers will get to the point where they run out of NDL before they run out of gas on a nice big single tank.

Isn't it great the the solution to a problem is to dive more instead of tossing money at it?!