Just bought a pony system, need help with answers...

[rakjar]

I just bought a pony system for and alternate air source, due to an out of air experience I had.

Thank to my dive buddy having a alternate air source, I surfaced just fine. I am now sold on the idea of having a totally different back up air source.

This brings up several questions though.

1. Now that I am using my octo for the pony system, would anyone advise also getting a safe second for my SeaQuest ProQD BC?

2. Does anyone advise the use of a guage with the pony system? I have heard both yes and doesn't matter. Which one, yes or no?

3. When going on vacation, I can either disconect my octo from the pony or buy a second octo so I can take my full reg system with me.

# 3 is assuming I don't take the pony with me on the plane due to the hassle of it.

Thank you.

Rob

 

[Scubaroo]

rakjar once bubbled...
Thank to my dive buddy having a alternate air source, I surfaced just fine. I am now sold on the idea of having a totally different back up air source.

Can you clarify what your buddy's "alternate air source" was? Was it a pony bottle, or an octopus attached to his first stage, or his primary regulator donated from the mouth?

I'm afraid you might be in for a beating with this thread - you've brought up out-of-air and pony bottle in the same post...

 

[Doc Intrepid]

that perhaps Lesson #1 from your experience should involve the importance of gas planning and dive planning!

The alternate air source is Lesson #2.

If you've resolved to carry a pony bottle, it likely makes the most sense to set it up like this:
http://www.dive-rite.com/resource/stage/index.htm

You needn't buy their kit to do so. You can rig it for under $15-20 worth of parts from your local Lowes or Home Depot, including bolt snaps.

While you're reading up on gas planning, calculate your SAC rate (Surface Air Consumption) and RMV (Respiratory Minute Volumn). Why? It tells you how big a pony bottle you might need. You may be interested to know how many cubic feet of gas it will require you to ascend slowly from, say, 100' with a 3 minute safety stop. Then you pick the best bottle for your need, rather than adapting your need to whatever bottle you buy. (Since you cannot predict your need with precision anyway.)

You will be best served by purchasing a second 'octopus' for your regulator rather than a BC inflator/regulator. You quite likely will NOT need a SPG on your pony regulator. Why not? Because should you ever find yourself hitting the pony, you will immediately be ascending. You (now) know precisely how much gas was in it when you descended, and what you'll need to ascend. No need to watch the needle drop on the way up.

One thing about pony bottles (like most of your gear). They only work in emergency situations when you practice with them frequently in NON-emergency situations. This includes deploying the hose and turning on the gas, re-stowing the hose and shutting down the gas, removing the bottle and handing it to your buddy, taking it back from your buddy and re-clipping it to your harness, etc. Every dive. It can be a huge PITA.

But if you don't work with it, then its a false sense of security. Which is more dangerous than not having it at all.

Best,

Doc

 

[DA Aquamaster]

This may be controversial but an Air 2 or something similar is an ideal way to add an alternate second stage to your primary system. It saves an extra hose and more importantly another second stage that could be confused with the pony's second stage in some configurations.



I used a pony for years without a gauge on the reg but checked it frequently with a small hand held pressure gauge designed to check tank pressure. (they run $25-$50)

You can check it prior to each dive with your primary reg before the dive, but over time this will drain quite a bit of air out of it and is a bit of a pain.

You can also add a small button style gauge to the first stage. ($25-35) These don't work underwater as you cannot really see them if your pony is backmounted and they are only ballpark accurate but would work on an adequately sized pony for quick and easy pre-dive checks.

After a low air situation on a dive plan gone badly wrong due to sharing air with another diver who had badly planned, I had to use my pony during deco, I had an epiphany on the value of an SPG for a pony system. From proper planning and knowing my air consumption, I knew there was more than enough air in the 30 cu ft pony to complete the deco. But that is not really a substitute for seeing proof on an SPG. Sometimes just being able to see and confirm what you have left in the tank is pretty priceless. I added an SPG by the next dive and then shortly after figured I could just as well go with independent doubles with the same equipment and virtually the same configuration and have more air and more flexibility with equal redundancy and very little extra weight.

What is right for you depends on you, the type of diving you do and what you are comfortable with. You need to remember though that a pony that has, without your knowledge or permission, slow leaked all it's air since last weekend when you filled it does not constitute a redundant air supply.



Most octos can be switched between first stages as long as the intermediate pressures are close (within a few psi) or alternatively if the second stage to be switched is:

1) Tuned for use on the first stage with the highest IP, or

2) Detuned for satisfactory (no freeflow) use on both first stages, or

3) Adjustable and tuned with adequate range to work well on either first stage.

Any competent tech can set this up for you if you explain what it is you want to be able to do.

 

[Karl_in_Calif]

My own general calulations for ponies give the following, regarding size:

6 cu ft pony is good to 45 ft

13 cu ft pony is good to 115 ft

20 cu ft pony is good to 165 ft

30 cu ft pony is good to 185 ft

Diving deeper than 185 ft requires doubles with a manifold and isolator. This would be a technical deco dive.

On your question about putting an SPG onto the pony, my pony always has one. The hose for the pony SPG is the short 6 incher.

On your question about having an octo on your primary reg, even though you are diving with a pony; I always dive with an octo that consists of a full service high performance 2nd stage, even though I also have a pony with me as well.

Your octo is for your buddy. Your pony is for you.

 

[Scubaroo]

Karl_in_Calif once bubbled...
Diving deeper than 185 ft requires doubles with a manifold and isolator. This would be a technical deco dive.

Rob,

Don't let this statement fool you into believing you can safely dive to 185' with a single tank and a pony.

regards

 

[Uncle Pug]

rakjar once bubbled...
I just bought a pony system for and alternate air source, due to an out of air experience I had.

Glad you made it OK.

But let me be frank and to the point with you. You are going about this the wrong way.

Your problem was running out of air. You need identify why that occured and take steps to keep it from happening again. Just adding a pony to the kit will not solve your problem... it will only get you into your problem deeper.

So... why did you run out of air?

 

[rakjar]

I admit, I did not plan as well as I should have. The problem on that dive was two fold. First, I am a fairly new diver, 14 dives so far. I have had some problems locating a buddy who can dive when I can.

I met someone through NW Diver.com buddy board who is an experienced diver. However, we went to 112 feet on a wall that he had dove almost a 100 times before. This was almost double what I had done before and I was ok with it. The problem was I thought we were going to do a direct ascent and my buddy went the more safe, contour of the bottom route.

We should have started up sooner due to the fact we did not go straight up. Now having said that, I ran out of air at about 10 feet and after our three minute safety stop was over. Watching my computer, I knew I was low and had my buddies octo in my hand just in case.

That brings up the second of the two problems. When diving with a new buddy, the plan needs to be discaused and understood by both parties. We appairently were on different pages at that time.

Having a pony system is not a fix all, just an extra little air when or if needed. As far as the gauge goes, it seems like to me that even if you start you ascent at the time you need to use your pony, it is a good piece of information to know where you are in the whole sceme of things. Just a thought though.

Again, thank you for your advise, keep it coming.

And rest assured, I learned from that dive and since then have had several really good dives with no problems.

 

[Karl_in_Calif]

Scubaroo once bubbled...

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quoting Karl_in_Calif...
Diving deeper than 185 ft requires doubles with a manifold and isolator. This would be a technical deco dive.
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ScubaRoo's bubbles:

Rob,

Don't let this statement fool you into believing you can safely dive to 185' with a single tank and a pony.

[/B]

I never said HE was safe diving to 185 ft with his brand new pony.

In nontechnical PADI diving, you may very well stop all conversations at 130 ft, which of itself is probably 30 feet more than is probably safe. I cannot speak for PADI's tec-rec protocols. Since you are PADI diver, ScubaRoo, you are most certainly coming from their perspective, whatever it is.

The comparison I presented was meant to contrast pony bottle sizes.

Some people think you need a 30 cu ft pony to dive to 100 ft.

 

[Uncle Pug]

rakjar once bubbled...
I admit, I did not plan as well as I should have.

And that is not to fault you... but now is the time to start learning about gas management.

You need practice planning your dive based on the amount of air you have available (among other things) and then making your dive conform to your plan.

Just adding more air to the equation... especially in a pony tank... will do nothing for you in that regard.

I suggest you read this Scuba Board thread on Gas Management for a starter and then come back with some questions:
http://www.scubaboard.com/showthread.php?s=&threadid=15434

And in the mean time... pay no attention to the fellow in the Klown Kostume.