Pony bottle 19 oe 30?

[FOWLER267]

I have a spare reg and the redundant air supply "DUH" lightbulb finally clicked on...

I'm thinking about a pony. I figure that a 30 would be better if both are un- noticable. I would eventually like to work on some of the deeper tech stuff and I figure that if you ever need it; a 30 would be a blessing even if you can make it up on a 19... The wee bit of extra air might allow for a short safety stop.

Whats the opinion of those who use a pony and especially those who have tried both sizes?

[jfjf]

A 19 is probably enough if you are going to be doing no-deco dives. If you are going to be doing planned deco of more than a few minutes, then a 30 (or larger) would probably be better.

[SpearMax]

Originally Posted by FOWLER267

Whats the opinion of those who use a pony and especially those who have tried both sizes?

Generally, I think 30 cubes is not needed for emergency bail-out, unless you are an air hog and pretty strong. But, if you feel better with it, then do it. I use 19 cubers for emergency air bail-out which I did once from 200 feet. I use other 19 cubers for deco bottles requiring only 15-20 minutes of 80% oxygen at 30 feet or above. For much deeper stuff I have 45 cube deco bottles. For trimix dives to 300 feet or more, I have two 80 cube bottles for travel gas and deco gas. It does boil down to personal preference and factors like your SAC rate and your emergency strategy.

[snokat]

Tony and Jim are on the mark with a 19cf bottle, you will be heading to the surface straight away if your main goes haywire.
I just bought a 30cf myself, they do make a better deco bottle, but mainly for the versatility. Seems that dives in excess of 100swf are becoming more of the norm for me since moving to FLA and some of the wreck options require some staging as well.
After 39 years of diving I guess it was time to eliminate a variable, now 140-160swf doesn't have quite the cause for alarm.....just don't tell my wife.
Back in my early days I dove twin 50 galvis when it was the only option between a 71 or twin 71s. It was nice to see 100s come out, if you have ever dove twins you know what I mean. When I bought my present HP100s they came with the Genesis valve that takes an H-valve.....I will NEVER do it though. The weight on a rolling deck is a real hand full, for caving it is a different story.
Bottom line is, it's all about minimizing the risk.
Last note, in 1969 I dove with one reg & one tank, now it's three regs and two gas supplies.

[mjphawk]

Here is a thread I started a while back with some good info. http://spearboard.com/showthread.php?t=30707

I dive a 19cu for a bail out bottle. I can't imagine lugging a 30cu if I didn't plan on doing any deco. Just a note, an 80cu tank with 500psi is 13cu of air. Its plenty of time to ascend from recreational depths and do a 3 min safety stop. I have the 19cu that I use for a bail out bottle and that is quivalent to a little over 700psi in an 80cu. I went with the 19 over the 13 because they are the same diameter just a little taller and the weight difference was negligible.

[HeadHunter]

Fowler,

The 30 CF is probably too large for the type of situation you're talking about. If it's a pita to wear and handle..chances are, you won't.

The 19 or 13 cf alum's are both a good choice for a BOB for normal rec diving.

Another option you might want to consider is the Luxfer 14. This is a 2015 psi alum tank, instead of the more common 3000 psi alum tanks. It's slightly smaller than a reg 19cf tank. The advantages are that it's about 2 lbs. more positive when either empty or full and weighs about 3 Lbs less on the boat than a 19. Also, it's easier to top off something to 2000 instead of 3000.

If you're diving a steel main and you're always negative, then the 14 might be a good choice. If you're diving an alum main, than maybe not.

Either the 13-14-19 would work for what you're trying to do...I'd borrow a few from a buddy or two and try them out for yourself. Whatever feels "right" is probably the way to go.

Make sure you go with a quality, easy to use attachment. Again, if it's a major pita to use..it'll end up not being used. I personally like the Zeagle pony straps..they've done an excellent job for us.

If you're doing strictly, rec depth, no staged deco diving....than I'd keep it full of whatever your deepest mix is.....if you dive air, than have air in your BOB. If you never dive over 32%, than 32% in the BOB would work. Keep it simple. Some guys will tell you to have higher O2 than your main contains in it....no....it's not supposed to be a stage bottle or a planned deco bottle....it's a BOB. If you're planning on doing staged deco or higher level O2 blow offs....than it's not a BOB and thats a whole diff story.

The last thing you want in a difficult time is trying to remember what mix you have in your BOB.....

Dan

[IRONHEAD]

Lot's of great advise Dan, I dive a 13cf with zeagle strap I love it. I have ascended from 120' and had 1500 psi still in it at the surface with a safety stop as well. this setup is plenty for a bail out bottle. if your doing deco then get a bigger bottle but if not get something you will actually want to dive. I dive my pony on all dives and I think if it was a 19 or 30 that wouldn't be the case because paired with a 120 it becomes a real beast in the boat suiting up especially in rougher seas. God forbid you have to lift it over the gunnels after a dive.

[mjphawk]

Originally Posted by HeadHunter

If you're doing strictly, rec depth, no staged deco diving....than I'd keep it full of whatever your deepest mix is.....

The last thing you want in a difficult time is trying to remember what mix you have in your BOB.....

Dan

Well there you have it from the man himself. I forgot to mention that. I keep air in my bottle. That way no matter how deep I am I know I am ok to breathe off of it. It also makes it really easy to convince the guys at the dive shops to top it off for free.

Originally Posted by IRONHEAD

I dive my pony on all dives and I think if it was a 19 or 30 that wouldn't be the case because paired with a 120 it becomes a real beast in the boat suiting up especially in rougher seas.

I don't necessarily completely agree with this statement. The 19 is only longer than the 13 and once attached to my tank I don't even notice it is there. I would have to look at the characteristics again, but I think it is only about 2lbs different which I took out of my BC. JMHO. I don't think I will ever regret having the extra volume of air.

[snokat]

Hey Mike, I mentioned versatility in my post. One more reason for ME was that in cases when using an 80 the 30 is ideal. I dive an 80 as a last tank on 3-tank or more dive trips.

[SpearMax]

Fowler, Dan brings up a good mix point. I only use air in my BOB, but I go very deep all the time. Like he said, I sometimes see guys with high mixes in these extra bottles with them thinking deco sometimes BOB other times. If you analyze dive accidents, breathing off the wrong mix at the wrong depth is a sure fire quick path to the grave.

[ObieWan2bWet]

My honest opinion, if your buying a bail out and going to be be spearfishing with it, then go back mounted and get a 19. The diff between a 13 and 19 is negligible in all categories except air volume, more is better.

Also IMHO, there's no reason to run anything but air in a bail out bottle. It only has one purpose, to get you safely to the surface under controlled ascent in an emergency OOA situation. Like Dan the man said, if you use it for anything else, than its not a BOB.

One other thing to mention is to occasionally use the bottle up on a last dive of the day at your safety stop, (just like you should with your safe second reg/octo) even better yet, once every handful of dives, do a mock OOA ascent on the bottle. Couple reasons to do this, 1- you actually keep the reg/first in good working order by using it, and any problems with the equipment are detected and fixed quickly, hopefully before you actually need it. 2- You become very comfortable with your emergency OOA procedures, and lastly by using it, you'll also keep fresh air in it by refilling it.

[jfjf]

I also wonder that if someone felt impending oxygen toxicity at depth, that immediately switching over to a pony filled with AIR, and pressing the "up" button might add a little bit of safety in this unlikley scenario?

[ObieWan2bWet]

I've personally never heard anyone talk about feeling an O2 tox coming on, (probably 'cause its hard to talk when your dead)... never had it happen to me, so I can't say from experience, but from everything I have read and been taught it happens in an instant with no time to react, just boom... lights out.

... and I thought it was the "easy" button...

[SpearMax]

Originally Posted by ObieWan2bWet

I've personally never heard anyone talk about feeling an O2 tox coming on, (probably 'cause its hard to talk when your dead)... never had it happen to me, so I can't say from experience, but from everything I have read and been taught it happens in an instant with no time to react, just boom... lights out.

... and I thought it was the "easy" button...

Mike, you could have the symptoms other than convulsion. Remember the famous Acronym CONVENTID for oxygen toxicity signs and symptoms?

CON = Convulsion
V = visual impairment
E = Ears ringing
N = Nausea
T = Tingling
I = Irritability
D = Dizziness

I am going from pure memory here, but I think that is what each letter stands for. Obviously, it CON hits you first, you better hope a buddy is nearby. But, I (and people I know) have had one or two of the other signs and changed what I was doing immediately (e.g. go up in the water column).

Food for discussion, Tony

[ObieWan2bWet]

Originally Posted by SpearMax

...

V = visual impairment
E = Ears ringing
N = Nausea
T = Tingling
I = Irritability
D = Dizziness

...

Damn, I "VENTID" all the time... I thought that was just from having teenagers...