Pony tank thoughts/advice?

[Marie13]

I’ve never had to adjust my weighting to account for pony. I sling a 40 when single tank diving.

 

[sonofzell]

Ah, one other question: In the thread linked by Marie13, there are several suggestions for purchasing a "transfill whip". I confess that I'm not familiar with this device, but at a glance, it appears to allow the transfer of air from one cylinder to fill another(?).

If my assumption is correct, it makes perfect sense. With the perspective of the pony being an emergency backup, I hadn't really considered filling it with any frequency, but I guess I need to expect to suck air from it in order to practice. Are these "whips" as simple to operate as they appear? Would there be any safety concerns with attempting to refill the pony from a full-size tank at a dive site or on a boat?

 

[Cio]

I recommend mounting the tank instead of slinging it to beginners, this way the least amount of things change. I'm not arguing the benefits of a slung bottle but rather the benefit of progression, it is pretty unlikely a hand off is a good idea for beginners in an emergency situation, staying together should be advised, mounted tank ensures this .

If you have an air integrated computer, you can run a gauge off your pony to your left d ring, so you can check on it, makes a pretty clean setup.

Center of gravity is not the correct term in relation to this discussion, its called a moment and will not be enough difference to make it a consideration, this is easily offset with a little lead. If the addition of a pony induces a sever roll, you have a weighting issue you should address.

The most important thing is to make sure that it does not interfere with your BCD, if it doesn't let the bladder expand, this will cause a roll you can't fix, its also easily see by a dive buddy so should be on your setup checklist.

My recommendation, mount it to your tank, get a 5 foot hose on your primary, and short on the pony with necklace, play with that for a while, it should be an easy transition and be a nice comfortable way to assist another diver in need with minimal workload.

 

[Marie13]

I recommend mounting the tank instead of slinging it to beginners, this way the least amount of things change. I'm not arguing the benefits of a slung bottle but rather the benefit of progression, it is pretty unlikely a hand off is a good idea for beginners in an emergency situation, staying together should be advised, mounted tank ensures this .

If you have an air integrated computer, you can run a gauge off your pony to your left d ring, so you can check on it, makes a pretty clean setup.

Center of gravity is not the correct term in relation to this discussion, its called a moment and will not be enough difference to make it a consideration, this is easily offset with a little lead. If the addition of a pony induces a sever roll, you have a weighting issue you should address.

The most important thing is to make sure that it does not interfere with your BCD, if it doesn't let the bladder expand, this will cause a roll you can't fix, its also easily see by a dive buddy so should be on your setup checklist.

My recommendation, mount it to your tank, get a 5 foot hose on your primary, and short on the pony with necklace, play with that for a while, it should be an easy transition and be a nice comfortable way to assist another diver in need with minimal workload.

Really?

 

[RyanT]

Are these "whips" as simple to operate as they appear? Would there be any safety concerns with attempting to refill the pony from a full-size tank at a dive site or on a boat?

Yes, very simple to use. There's no safety concern filling from a full-sized tank. However, I'm not sure you'd really find a transfill whip necessary. You won't be filling your pony a lot and it's just as easy to drop it off for a fill when you have your main tanks filled.

If the addition of a pony induces a sever roll, you have a weighting issue you should address.

It's not a severe roll, but it places a few pounds on the side of your tank that is centered on your back. It's not a huge deal, but you either have to compensate for that with lead on the opposite side or you use your muscles to continuously correct the tendency to roll. Using your muscles to fight it is just annoying. By slinging the tank, you get the weight of the tank below your wing and you can pull it closer to your midline, hence reducing the roll. It's also not necessary to give a pony away in an emergency when slung. It can just stay clipped in where it is when deployed.

 

[RyanT]

@sonofzell, here's something else to consider. One of our members here was pretty vocal about not liking pony tanks. His concern (and I agree) is that if your main reg has your primary plus an octopus, then you add a pony, you now have two alternate second stages and that could generate confusion in an unexpected emergency. If you're going to go the pony route, it's better to take off your octopus and practice using the pony reg as your alternate. Of course doing so means you need to carry the pony on every dive or be prepared to add your octo back on dives where you aren't carrying it.

 

[johndiver999]

@sonofzell, here's something else to consider. One of our members here was pretty vocal about not liking pony tanks. His concern (and I agree) is that if your main reg has your primary plus an octopus, then you add a pony, you now have two alternate second stages and that could generate confusion in an unexpected emergency. If you're going to go the pony route, it's better to take off your octopus and practice using the pony reg as your alternate. Of course doing so means you need to carry the pony on every dive or be prepared to add your octo back on dives where you aren't carrying it.

This issue ONLY arises if the diver back mounts it. If they sling it, then second stage confusion is not an issue. Also a whip is VERY handy on a boat to top off a leaked pony or even for use on main tanks. It is very useful to get a whip that has an integrated gage.

As for a back mounted 19 cu-ft tank rolling you over, that is not something I have expereinced.

 

[Gareth J]

If you are talking about a small cylinder (3 litre), then normally I would have it strapped to the cylinder. Even when we where using 3 litre cylinders for Nitrox 50, I still strapped it to the twinset, in preference to carrying it as a side slung.
7 litres and up, I would carry as a side slung.

A single and pony is still a very standard rig in the UK. Especially for those that aren't interested in deeper diving, or have no intention of upgrading to a twinset. (There is the advantage that they take up less space on a RIB than a twinset.)

If you are carrying a pony (or stage), get used to swapping from primary gas onto the pony (and back). Traditionally unlike a stage, a pony is a bailout rig, so always turned on ready for immediate use. Be certain you can differentiate the pony regulator from any other, and make sure its a good quality first and second stage, you are going onto it when the primary fails, so you want to be certain it will work.
Always keep the pony full, or its useless.

Down to about 30m a pony is a valid bailout, much below that, a twinset is a better choice.

 

[-JD-]

@sonofzell Welcome local friend!

I dive Dutch pretty regularly (mostly, actually). Given my experiences there (Dutch) with buddies (ranging from insta-, to regular, to instructor) and with insta-buddies in the Caribbean, I have come to the conclusion that I am almost always diving (effectively) solo and, therefore, I am now always diving with gas-redundancy - either a pony or twins.

I'm of the "sling" camp with the pony and I dive it "hot". I turn it on and test-breathe it at the start of the dive day. Before each dive, pressure is checked with the button gauge and "on" state is confirmed with a twist - I also use "Vindicator" knobs on my ponys for easy visual confirmation.

I dive with a "standard" regulator configuration for my back gas ("primary and secondary/octo") and because the pony regulator is tucked on the pony bottle, there is no confusion about which is which.

Immediate donate to an out of gas (OOG) diver is from my back-gas because that always works - pony or no pony, single or twins. The pony is primarily for me, but would give me the option to unclip it, transition the other diver to it and then separate myself from the OOG diver if circumstances should warrant.

Roll with a slung 19cuft pony is negligible, but when diving singles, I do use 5 pounds of high-mounted (upper camband area) trim weight and I use a 2 on the left (pony) side and a 3 on the right which gives me a little counter balance).

A transfill whip is not an absolute requirement, but it is nice to be able to just top off the pony after a few rounds of test breaths. Since I'm usually diving HP100s or 120s, a quick top-off is no issue.

I'm near Norristown. If you are reasonably close and want to check out my pony setups (I have a 19 and a 40) in person and see if it will work for you, feel free to reach out. We could also probably pick up a stage kit (or the parts) up at Northeast Scuba Supply and get your bottle set up for you. I believe John (at NESS) also may have some used tank brackets if you decide to go that route.

 

[lexvil]

No magic, a pony gets in the way a little out of the water but pretty much disappears in use. You can easily make the set up yourself with just a few bucks in parts, switch to DIN for a cleaner rig.

You can make a hose retainer with nothing more than some bungee.

The pony corral