Pony bottle

[rabe]

...next on my bucket list is a pony bottle: I'm not an air hog, but I think is better have one, especially for deep dives.
Any suggestions regarding brands and other tips?
T(h)ank you!

 

[RayfromTX]

Will you include it in your gas planning or is it strictly for backup?

 

[rabe]

Backup for the moment...

 

[rhwestfall]

 

[Marie13]

Here's my thread from last fall. Cost is in USD, but the info will still be applicable. People get rather opinionated on the topic. I carry an AL30 as my pony. Works for me, may not for others.

Cost of pony setup?

 

[rabe]

Thanks Marie!

 

[rhwestfall]

People get rather opinionated on the topic.

passionate is the word I'd use...

 

[rabe]

People is often "passionate"

 

[2airishuman]

...next on my bucket list is a pony bottle: I'm not an air hog, but I think is better have one, especially for deep dives.
Any suggestions regarding brands and other tips?
T(h)ank you!

There are four main questions you will have to answer.

1) How are you going to carry it
...a) slung
...b) on your back attached to your primary cylinder
...c) in a pocket

2) How big, the practical choices are from 1.5 cf to 40 cf

3) Where is the reg

4) Are you carrying valve on, or valve off.

Brands, etc., are secondary to all this.

There is widespread consensus on ScubaBoard that the Spare Air 1.5 and 3.0 cf cylinders are simply too small to provide sufficient redundancy across a reasonably wide range of typical recreational dives. Aluminum cylinders in 13, 19, or 40 cf are the usual choices, and the appropriate gas planning approach and therefore the proper size to select is highly controversial on ScubaBoard. I usually use an AL19 but do have 40s and twinsets available for dives where I believe the AL19 would be insufficient.

I believe that the safest and best configuration in most situations is to sling the pony cylinder, that is, attach it with snaps to a chest and waist D-ring. If your BC does not have d-rings in these locations they can be added fairly easily. This is the method technical divers generally use to carry a stage cylinder, something that is done widely, so it is a configuration whose safety is well understood. With this configuration the regulator is stowed on the cylinder using elastic bands, and the cylinder can be carried either valve on or valve off.

For people who do not wish to sling a cylinder, particularly divers who spearfish and need to keep the front and sides of their body uncluttered, it makes sense to back-mount the pony cylinder by attaching it to the primary cylinder or the cam bands. The best way to do this is to put the pony regulator on a necklace and use an integrated power inflator (Air2 or similar) for secondary air on the main cylinder. Whatever regulator setup you choose, it is vitally important to be sure that you can determine which regulator is for the pony and which is for the primary cylinder. There have been fatalities as the result of mixups. One of the drawbacks of this configuration is that the valve may not be reachable, and a button SPG will not be visible during the dive.

If you carry the pony with the valve off, it is important to use a DIN valve and regulator because a yoke valve is more likely to come loose during the dive and because it is possible to mistake the yoke nut with the valve wheel in an emergency leading to accidental detachment of the regulator when trying to open the valve.

I use the same regulators on my (slung) pony that I do on my primary cylinder, with a 40" hose, and a button SPG. Some people use valve-integrated regulators like the one on the H2Odyssey Extra Air Source. You can buy these by themselves from various sources and choose a cylinder of any size to use with them.

Hope this helps.

 

[rabe]

Thank you 2ari, very useful!
Quick reply:
1) I will sling the bottle and/or attach it on the side of my BCD (Oceanic excursion, which has D rings on the side for that purpose)
2) My choice is on a 19: I think is a good compromise (not too small to have not enough air, but not too big to bother me)
3-4) My idea is to use a completely different reg with DIN and a small SPG. The reg will be hold by a band around the pony, like in this picture https://images-na.ssl-images-amazon.com/images/I/513oqpVnLzL.jpg (sorry, I couldn't find any better, but that's the idea)

...it doesn't look to much different from what you're suggesting.