Octopus recommendations

[NudeDiver]

I bought an AirSource-2 when I bought all my crap in 2003. Since then, I've figured out that although it is nice to avoid and extra hose and such, the AirSource-2 sucks as a second regulator, for all the obvious reasons. So, I am looking to replace it with an Octopus that I can wear on a necklace.

My primary is a ScubaPro MK25/S600. I got this because I live in Alaska and reliability in cold water is a must. It was pretty expensive. From what I've seen, Octopi are a lot cheaper. I know part of the reason is because they do not come with a first stage - but even so, that doesn't seem to account for all of the cost difference. So, my questions are:

a). Can someone recommend an Octopus suitable for cold water use (I live in Alaska)?

b). How much should I expect to pay for a hose short enough to use the Octo on a necklace?

c). Why are Octopi SO much cheaper than primary regs - even factoring in the cost of the 1st stage?

d). Does it make sense to spend extra on an Octo, or should I just get one of the cheaper ones?

e). Should I bother to keep the Airsource-2 once I get the Octopus, or should I just put the regular inflator (never been used) back on?

Thanks!
ND

 

[RJP]

My primary is a ScubaPro MK25/S600. I got this because I live in Alaska and reliability in cold water is a must. It was pretty expensive.

Any reason to believe that your back-up regulator requires LESS reliability?



Be selfish here and remember that the back-up is the one YOU have to breathe off -whether a failure of your primary or in the event of an OOA buddy. In very cold water I'd suggest going to an H valve set-up and having redundant FIRST stages as well.

I'd say go with the same reg for primary and secondary. Makes them interchangeable from a rotation/service standpoint.

PS - If you have any inclination to go to doubles bite the bullet now and buy a whole first/second stage and be done with it!

 

[NudeDiver]

Any reason to believe that your back-up regulator requires LESS reliability?Be selfish here and remember that the back-up is the one YOU have to breathe off -whether a failure of your primary or in the event of an OOA buddy.

No - and this is precisely my point and why I am asking. It seems that Octopi are so much cheaper than primary regs. My big question is, since it should be just as if not MORE reliable, then why is this? Is most of the cost REALLY in the first stage? This is really the heart of why I am asking.

 

[RJP]

No - and this is precisely my point and why I am asking. It seems that Octopi are so much cheaper than primary regs. My big question is, since it should be just as if not MORE reliable, then why is this? Is most of the cost REALLY in the first stage? This is really the heart of why I am asking.

Many "octopus" specific regs are stripped down versions of their "primary" counterparts. Beyond not having a first stage they frequently lack some of the adjustment knobs/features found in the primary version.

I'm not terribly familiar with the SP line, but there's quite likely a "primary" reg second stage that's a model or two down from your primary that would serve you well as a backup while preserving the performance and reliability of a dedicated "primary" reg.

 

[Jimmer]

Have you dove the Mk25 in the cold yet? It has a bad reputation around here as a cold water reg, and I know several Great Lakes divers that I dive with that had gotten rid of them due to freeflow problems.

 

[NudeDiver]

Have you dove the Mk25 in the cold yet?.

Yeah, sure. I certified in a slushy mix of ice and water in Alaska with it in November. Have about 20 cold-water Alaska dives with it, not even a hint of a problem with it.

 

[maged_mmh]

SP R295 has a fair price & good reliability

 

[Web Monkey]

I bought an AirSource-2 when I bought all my crap in 2003. Since then, I've figured out that although it is nice to avoid and extra hose and such, the AirSource-2 sucks as a second regulator, for all the obvious reasons.

Unless you're doing an overhead dive of some type, it's probably as good as it needs to be, since if you're breathing on it, you're pretty much always less than 4 minutes from the surface (7 minutes if you want a safety stop)

So, I am looking to replace it with an Octopus that I can wear on a necklace.

There's nothing wrong with that, but if you're going to buy a cheap reg, what you have is probably as good as what you'll buy.

a). Can someone recommend an Octopus suitable for cold water use (I live in Alaska)?

The Atomic M1 is nice and is designed for cold water.

c). Why are Octopi SO much cheaper than primary regs - even factoring in the cost of the 1st stage?

There's no free lunch. A good part of the cost is the first stage, part of the cost is is covered by the missing features (adjustments, etc.) however a lot of them are just cheap regs that you wouldn't ordinarily want to breathe from.

d). Does it make sense to spend extra on an Octo, or should I just get one of the cheaper ones?

That depends on what you want to be breathing when the brown stuff hits the fan. I can tell you that if you're OOA, there's a good chance that the OOA diver will take your primary, especially if he takes your backup and doesn't feel like there's enough air coming out of it.


Terry

 

[goldenwingk]

a). might aswell go with a scuba pro still maybe a R295 thats what i use for my MK17/G250V and i dive in cold/ice water too.
b). you should stick with the longer hose, the long hose helps as it allows the air flowing to the second stage more opportunity to warm up. you might want a longer hose on your primary too, but thats just an option.


The Mk 25 has its own cold water problems as the TIS system is not quite up to the hgeat transfer/freeze prevention task in extremely cold water (below about 45 degrees) unless your cold water technique is perfect. When you combine it with an S600, with its small plastic case and plastic air barrel, you can have bigger problems. A very slight freeflow in the second stage caused by formation of small ice crystals can create just enough extra flow to cause the Mk 25 to begin forming ice in areas that ultimately result in a large freeflow

 

[KarolinaKid]

Lot's of good advice thus far. I dive with an MK25/X650 and have never had any problems at all. My coldest dives have only been in the 40's however. If you are happy with your current setup and plan to continue cold diving, then buy another just like it, get an H valve for your tank and dive with a redundant 1st and second stage (like RJP suggested). Or, get an MK17/G250 as your redundant set as they seem to get a better cold water rating (perceived anyway).