using a pony bottle to extend bottom times?

[nimoh]

unfortunately I cant...everytime I drain my tank...the scuba shop charges 20 dollars for a visual inspection. So yes I could do it, but then if I wanted to swap back and forth id be screwed. I like the idea of 40cf for 80-100ft dives. I like the idea of 19cf for shallower so id want to eventually have both but for right now ill stick with the 40.

---------- Post added June 30th, 2015 at 04:05 PM ----------



I didn't mean just a tank but the whole setup.

The tank I linked to includes a Sherwood valve. You don't need to drain the tank to switch regs.

 

[Wookie]

seriously not trying to start a war here but what if one guy showed up with a single 100 steel and his buddy had an 80 and a 30cf stage...both want to do recreational dive...you are saying the guy with the 100cf steel is ok but his buddy with an 80cf and a 30cfstage is not? I am just playing devils advocate here.

You nailed it.

---------- Post added June 30th, 2015 at 05:15 PM ----------

OK, I have a question though, what if someone showed up with a set of doubles like twin 72's but only had one air outlet like a center post and treated the set like a big single. But let's say they like the balance of the twin 72's and buoyant characteristics better that say a modern mega single tank the size of a water heater. Would you consider that to fit the recreational criteria?
Because if they were filled to 2250 then that would be basically like a 130.

But we don't allow doubles or stages on recreational trips. We have trips for that. Recreational trips aren't those trips. If someone showed up with a set of doubles we would happily refund them. Or give them an 80 and a pony. But it would be very rare for someone to do that, because the policy is very clearly stated in our terms and conditions, and you must agree to the terms and conditions before I ever ask for your name.

---------- Post added June 30th, 2015 at 05:18 PM ----------

please let me know where I can get a pony setup for 130 dollars? Most setups I have seen (unless used) are in the 300-400 range?!?

The exact reason I got the 40cf was for what others stated...I will be hopefully moving into tech/deco dives in 2 years. Honestly the 40cf is the only thing I have slung and I have gotten quite used to it to the point I don't feel a difference under the water whether I use it or not. Out of the water is another story haha.

I think she was talking about 130 for a 40 and another 130 for a 19, as you need the same reg set for either.

I have a large number of folks who bring 40s as their pony. Way more than 19's or 13's. I almost never see a 30.

 

[TSandM]

So, you have a bunch of answers all across the board.

I think I would agree that a better answer to a bigger gas supply is a bigger tank. But if you are going out on boats or renting tanks from operators where you are diving, that might not be an option.

It is also better to work on the things that are causing you to use your gas so fast, but that takes time.

In the meantime, if you ARE going to use a slung bottle for extra gas, you should understand what's involved. First off, it is a generally accepted principle that you use offboard gas first. The gas on your back is reliably with you; the gas in an extra bottle is a bit less reliable, and therefore is used first. Be aware that, if you intend to breathe a 40 down to 100 psi or so, it will become positive, and this will affect your buoyancy.

Secondly, if you are going to breathe that tank first, and switch, you need to be able to maintain buoyancy, trim, position, and buddy awareness during the gas switching process. This takes practice, which should be done in shallow, benign conditions (even a pool) until you are sure of yourself. I find stowing stage regs to be a pain, myself, but you need to be able to do it quickly and neatly, so the stage reg does not become an entanglement hazard.

Third, your buddy needs to understand what you are going to be doing, so he can receive the signal that you are going to switch, and monitor you for any problems during the switch (for example, finding that your backgas wasn't turned on, or fumbling the change of regulator). Obviously, both tanks need to be properly labeled for contents and MOD as well. (This could be very important on a pony, since a lot of people might assume that a 40 has something other than air in it, and might grab your bottle if someone needed emergency O2.)

Wookie brings up a good point, that some operators might not permit you to do this, but if you are shore diving, it's pretty much up to you.

I see no problem with carrying extra gas, so long as you have the understanding and the skills to do it safely.

 

[uncfnp]

I am curious too how the average recreational dive operator would know unless you announce your intention. I have yet to have anyone check the condition of my pony before or after a dive.

 

[Wookie]

How many liveaboards have you made with a pony?

 

[dumpsterDiver]

Why would a new recreational diver use the pony/stage bottle first? The descent is often challenging, maybe going down an anchor line, dealing with waves and surface currents, difficulties in maintaining buddy contact during descent, they have to CAREFULLY watch the air supply if the descent is delayed by ear issues or a slow buddy.. etc..

Not that I have any training in any of this stuff, but if I were going to try to use the pony to extend the dive, I think I would go down on the big tank and once things mellowed out on the bottom, I have my buoyancy perfect, I have visual references with things on the bottom, I got my breathing rate down a little after the excitement and exertion of a descent, - THEN I would switch over to the smaller tank.. I think it would be simpler for me..and I would not be as task loaded on the descent. Also the need to stow the second stage on descent would be avoided as well.

 

[uncfnp]

How many liveaboards have you made with a pony?

Oh, you mean checking the ponies? You are right, I was not referring to recreational liveaboards.

 

[Wookie]

Oh, you mean checking the ponies? You are right, I was not referring to recreational liveaboards.

I wasn't trying to be snarky, but it's different on a liveaboard. We don't check pony pressure, because we don't really expect any one to use it. We will fill it if it does get used, it's safety equipment after all, but if it does get used, I want to know why. Is the person an air hog (and if I lend them my steel 100, will they have a better experience?), or are they having equipment issues (I carry an assortment of rebuild kits, but I'm kind of old school. Ask me to rebuild something from before 2005, not after), or are they unaware of their gas consumption (I'm happy to help calculate rock bottom, rule of thirds, RMC, SAC, or just watch your gage and come back with 500 or so PSI), whatever they need to make their trip enjoyable, and keep me from worrying about them.

I don't want to worry about you folks. I run a small business. I have enough to worry about.

 

[waterpirate]

Why? Why is your sac rate so high?
Until you know the answer, your looking for " a gear solution, to a skill/fitness problem " . Saying you are average shape means nothing. Cardio and comfort in the water is everything. Comfort comes in time with repetition and skill development. Cardio comes in time with excersise and stamina. Your issue boils down to one or the other or both. Eliminate 1 or both and you will be better for it.
YMMV
Eric

 

[Patoux01]

*Disclaimer: I didn't read through all the thread, as it seemed to go in a debate about whether you should do 61 or 59 seconds stops, or whether you should call it a stage or a horse (pony, pun intended).
This is my opinion *

Using the pony is fine. You just have to be "smart" (not stupid would be a better term ).
As long as each tank has enough gas to get me out of trouble at all time, I'd have no issue breathing off a so-called "pony", call it a stage if you want, whatever, it's a tank.

No such thing as a "gas change procedure" imo, that's like me asking my buddy to stop when I switch regulators on independent twins, sure, go ahead if it pleases you, but I wouldn't.
Depending on his setup, he can simply bungee the reg of the pony on a necklace and using a longer hose on his main tank: there you go, no stowing of a reg, reg switch is as easy as can be (removing a regulator from your mouth is probably a skill from pool dive 2 in OW)

Oh, I'll add: knowing I have a massive amount of gas seems to make my SAC drop.