Octopus recommendations

[Groundhog246]

I carry a PONY bottle, not a 'Spare Air' (which in IMHO is worse than nothing, becuase you think you have a backup). Mine is a 30CF, which is over 1/3 the capacity of an AL80 or roughly equivalent to having about 1100PSI in an AL80. More than enough to do a nice slow ascent form 100 feet, including a deep stop (I've started doing about 2 minutes at 50% of max depth on deeper dives) and a stop at 15 feet.
I carry mine slung like a stage bottle, I can deploy the reg and breath on it, without unclipping, so no risk of dropping it. In a pinch I could unclip and pass to someone else. If I did so, there's a good handle on the side as part of the rigging.

I carry it in addition to my regular octo, as I only carry it on deeper dives. 4 weeks to service!!!! Unless they were hung up waiting for parts, that seems a bit much, even during the peak season. Checking the tuning (IP pressure, etc) and re/de-tuning the reg only takes a few minutes. Should be able to do while you wait, especially if you make an appointment.

 

[rescuediver009]

Go ahead and crack me over the head then. The pony bottle is NOT part of your gas management planning (according to my training). It's there as an emergency reserve, for when it's hit the fan.

Yes this is correct, I should have mentioned that the ponies I am referring to are above 19 cu. ft. in size. I can understand the little 13 or 9's for emergency, however, I do not see this with a sling bottle. You are only using it on your ascent when the dive is near completion anyhow.

Do you feel the same about the guy who never put his spare tire on his car? My wife and I have $250 each PFD's that we've never inflated (other than periodic manual inflate to test for leaks) and $400 worth of flares we've never used. I realy hope that we never do need to use either, but that doesn't stop me from carrying them.

No I do not feel the same, but I don't feel the same for the guy who has been diving and never had to use his octo either....

Also if you are the guy who is always limitting the dive due to poor air management skills, I would find it considerate. And while pony bottles for recreational diving are not considered part of your supply, I believe that training dictates that stage or sling bottles are all considered in your ascent especially when deco is in effect.

 

[BigJetDriver]

Can anyone recommend an octopus that won't cause me to run out of air unexpectedly?

Thanks.

Rimp,

One thing you can do is to fit a shut-off valve (a slide or trombone-valve) at the end of the hose where it fits onto the back-up second stage.

I would, however, suggest that Curt Bowen's recommendation is by far the better solution.

If you follow his suggestion, you will have a completely separate first and second stage, as well as a separate gas reservoir. The smaller cylinders, in the 19 to 30 cu ft range are easy to clip on, and you will not notice them when swimming.

Cheers!

 

[tangfish]

get a ScubaPro R350 mate!

 

[outlawaggie]

Can anyone recommend an octopus that won't cause me to run out of air unexpectedly?

Thanks.

I have a Mares Proton Octo. I've never had a problem with it. FWIW, I've breathed on it at 60' and thought it breathed as well as my primary (Mares Proton Metal)

 

[opiniongirl]

I have had the same problem with my Oceanic oct. The LDS first thought it was the way I had it mounted. It was mounted in a slip-on plastic mouth piece cover. They said that mount caused a differential pressure while diving. Turned out the reg needed to be adjusted. 10 dives on the oct at the time. Now it has 20 and I'm not convinced that it doesn't still have a problem. I don't know about your model, but I am replacing mine.

At least it makes you pay close attention to your air supply. Once you get it figured out, you will have developed a good habit.

On an aside here - if your octo is the "Swivel", they were having a major problem with the seats...
So no amount of fine tuning helped - I would see whether or not there is a recall on the specific octo seat you are using...

 

[Groundhog246]

Also if you are the guy who is always limitting the dive due to poor air management skills, I would find it considerate. And while pony bottles for recreational diving are not considered part of your supply, I believe that training dictates that stage or sling bottles are all considered in your ascent especially when deco is in effect.

Not generally, although I do have a couple of buddies who do use less air than me. Maybe your training dictates stage or sling bottles are part of your supply. For myself, I am not trained in deco (or other "technical" diving), nor do I desire to go there. If I need more air to extend my bottom time (within the no stop limits), I'll switch to larger bottles. In general, NDL and cold have been the limits to my dives, not air.

 

[DA Aquamaster]

My thought on octos is that they should be of equal quality to your primary second stage. Most likely you will be the one using it as even if you don't believe in donating your primary, odds are you will get mugged by the OOA diver and involuntarily donate the primary anyway.

Many second stages have flow vane adjustments knobs or dive/pre-dive switches that when set in the (-) position will not support a freeflow. Other second stages have adjustment knobs that can be tightened to de-tune the second stage to reduce the chance of a freeflow but still enable the beathing resistance to be lowered when you are using the second stage.

These are far better options than going with an inexpensive cheaply made non adjustable octo that breathes like a rock and may not deliver adequate air at depth.

 

[Groundhog246]

I have tried breathing from my US Divers (Conshelf) octo on the surface, shallow (20 feet) and deeper (60 feet) and I can't detect any difference in breathing resistance from my primary (Conshelf SE). Neither are adjustable.

 

[opiniongirl]

I have tried breathing from my US Divers (Conshelf) octo on the surface, shallow (20 feet) and deeper (60 feet) and I can't detect any difference in breathing resistance from my primary (Conshelf SE). Neither are adjustable.

The major difference in most regs between the primary and the octopus is...

THE SPRING!!

There is a stiffer spring on the octopus which will make it breathe "harder". This is to reduce the amount of free-flow. The conshelf is an excellent example - hardly a difference between the octo and primary, except for that spring. The body, and internal parts besides this spring are identical to the primary in most regulators.

Today, Octos with adjustability are easy to find, making it unnecessary to pile a ton of money into a backup primary. Yes, the el-cheapos will breathe stiffer than your primary (but you can tune that to some degree) but will still undoubtedly provide an easier ascent than buddy breathing...again - technical divers will be under a different set of requirements, but a good 'ol standard octopus is more than adequate for a recreational diver.