Pony Bottle Recommendations

[halocline]

Why do you feel he needs a pony? The dives you note are about as easy as they get.

A pony is pointless for what you describe and only going to add confusion.

What is pointless is what we or anybody else thinks he might or might need; the OP did not ask "do I need a pony for safety?" She simply asked for advice about specific pony options.

 

[Rocketmahn]

Why do you feel he needs a pony? The dives you note are about as easy as they get.

A pony is pointless for what you describe and only going to add confusion.

Dr Wu - I highly disagree.

A tank mounted pony is the perfect choice for this type of diving.

He is a photographer and solo diver. Solo divers should have redundant sources of air.

He may be so focused on waiting for his "subject" to move to the perfect spot or just the right light that he forgets to check his SPG and runs out of air.

He may have a slow leak (unnoticed since he has no buddy) and uses air much faster than normal and runs out of air.

He could get a load of bad gas or a low fill - mistakes happen.

His main tank CAM strap could come loose and the tank could slide down and out of his rig pulling the reg from his mouth and putting it out of reach.

He could have equipment failure etc..

I will agree that doing an out of air ascent from 60' is not that big of deal, but it certainly is MUCH easier if you are breathing.

I would back mount the pony on the BCD TANK STRAP and NOT strap it to the main TANK (in case the tank slips the pony and reg are still in the "normal" position).

I would get a 19 cuft al pony with a Thermo pro valve (DIN/Yoke), I would get a "Button" SPG that screws into the 1st stage (Diverite/OMS ~$20-$25), the regulator is up to you - I like the way that the DiveRite Reg hoses lay alongside the tank, I also would get a "necklace" for the 2nd stage so it is kept right below his chin for really easy access, and you need a Pony bracket that allows it to mount TO THE BCD STRAP!

The 2 nd stage should have a different mouthpiece than his main regulator so "it feels" different if he ever "inadvertently" starts to use it.

Also he may want to mount the tank upside down so he can easily reach down and back to double check the valve vs. having to reach up and over his head and down his back. But in the tropics, with a thin wetsuit he should be pretty flexible so it may not matter.

Remember, it's all about personal preference and comfort.

My $0.02. YMMV

 

[Crush]

Why do you feel he needs a pony? The dives you note are about as easy as they get.

A pony is pointless for what you describe and only going to add confusion.

I have to agree with others who believe that your premise is incorrect.

NAUI teaches that an out-of-air ascent from below 50 feet is dangerous owing to the possibility of a deep-water blackout, which is caused by a rapid drop in the partial pressure of oxygen in the lungs on ascent. Blackouts occur typically from zero to three meters (0-18 feet) below the surface and usually result in the unconscious victim drowning at the surface. The blackout is not certain to happen, and an OOA ascent is preferable to drowning at depth, but a pony might make the difference between life and death. Your note about confusion is a fair one, however, and the diver in question should regularly practice switching his air supply with his diving buddy present. One benefit of a slung pony is that you can transfer it to your dive buddy, should they be the one who encounters an OOA situation.

 

[Riger]

My 2c

I agree that to "judge" the concept of a second source of air under whatever circumstances the OP describes is off topic and out of scope of the question.

If the second supply is only intended for use as a back-up measure (not extended dive time) then the calculation should be based on the time required to access the second source, + conservative ascent time + stop time + comfort level %.

I have dived with a 7 Liter (front slung) occasionally on some deeper wrecks (30m) and even with camera equipment found it to be an easy adjustment. Having said that, I am not the smallest guy in the boat.

I like the previous suggestion of replacing the octopus with the second source, it make good sense to me.

Regards

Richard

 

[spyder]

Size all depends on depth, sac rate, and what you determine as an acceptable/reasonable situation that would require going to it (potential deco time). From there it can be calculated as to how much you might need. While I haven't actually dove with a Catalina I was told when looking for my deco tanks that Catalina's tend to be tail heavy will drag vs. Luxfer/Hymark that are tail light and naturally ride tail up when under an arm (at least in 40's). I went with Hymark and can attest they are tail light. I do some photography and having a 40 slung under the arm isn't cumbersome at all, don't even know it's there really. I tried tank band mounting with one of those aluminum quick draw brackets but found under the arm works better from a bouyancy/use standpoint. Simple, easy to use/check, and I could hand it off if needed. I agree a button gauge on the first is all you need. You want to know it's full when you go down and when you go/have to get on it you're heading up anyway. If there isn't enough....well....you tried.

 

[Dr Wu]

Dr Wu - I highly disagree.



........He may be so focused on waiting for his "subject" to move to the perfect spot or just the right light that he forgets to check his SPG and runs out of air......

You plan your dives with the possibility that you may run OOA because you "forgot" to check your SPG?

Anyone that considers this a possiblility should not be diving at all. No piece of gear will make you a safer diver.

 

[iztok]

You plan your dives with the possibility that you may run OOA because you "forgot" to check your SPG?

Anyone that considers this a possiblility should not be diving at all. No piece of gear will make you a safer diver.

Many cert agencies recommend pony bottles as part of extra redundancy for certain dives. Granted not everyone is a perfect diver like yourself.

 

[Dr Wu]

Many cert agencies recommend pony bottles as part of extra redundancy for certain dives. Granted not everyone is a perfect diver like yourself.

All cert agencies recomend not running out of air in the first place.

Perhaps you were out that day?

 

[Rhone Man]

Let's not fight in front of new members. If someone asks a question, I think it is legitimate to ask them "are you sure you really need that"? I'd almost certainly reply in those terms if anyone asked me to recommend an instructor for the PADI Boat Diver course.

For what it is worth, I don't think carrying a pony makes you any more likely to OOG than carrying a sausage makes it likely you will be unable to relocate the anchor line. Everyone decides what precautions they like to take.

 

[keithdiver]

You plan your dives with the possibility that you may run OOA because you "forgot" to check your SPG?

Anyone that considers this a possiblility should not be diving at all. No piece of gear will make you a safer diver.

SORRY WE ARE ALL NOT PERFECT DIVERS LIKE YOU!! IM SURE YOU HAVE NEVER , EVER MADE A MISTAKE IN YOUR DIVING CAREER