Using Poseidon Xstream 2nd Stage with Atomic 1st Stage?

[James Ocean]

Hi all,

Can I use a Poseidon Xstream 2nd stage with an Atomic Z2 1st stage?

I believe the Xstream uses a different pressure. Can the Atomic 1st stage be adjusted?

Anything else I should know?

 

[rsingler]

That arrangement is just fine. The Poseidon requires an IP around 121, and the Atomic can be tuned to that pretty easily, by using fewer shims.
No problem!

 

[axxel57]

Yes, from the IP adjustment generally it would be okay, but it might be a good idea to install an OPV on the Atomic 1st if you are diving it without a Downstream Valve Octo, since the Xstream has an Upstream Valve as also the Poseidon Jetstream 2nd has.......

 

[Dominik_E]

Second the point about considering an OPV if diving in a configuration where there is no other (harmless) release in case of rising IP.

 

[rhwestfall]

While the first stage OPV is a good generic comment, depending on the year and configuration, the OP may have a second with the OPV built into the factory hose...

 

[tbone1004]

If used with a standard second stage, there is no need for an OPV.

If you are only using Xstreams with the Atomic, then I would recommend spending the extra money on the Omniswivel hose adapters instead of the cheap ones as they also have an OPV built in and they're much more reliable than the cheap ones that screw into port plugs

 

[Bigbella]

While the first stage OPV is a good generic comment, depending on the year and configuration, the OP may have a second with the OPV built into the factory hose...

Good point; though, only the earliest of the XStream first stage models were without an OPV. I don't recall many after, say, 2006, that didn't allow for conventional hoses.

Of the XStreams that I have used, only the first stage, from that year, that I have used with my Atmosphere FFM, has the OPV in the hoses . . .

 

[rhwestfall]

I have no idea how old mine are..... purchased used. No idea how long the XStream has been in production, or when they switched to te design with an OPV in the first stage, but I thought it to be in the recent past...

 

[James Ocean]

Thanks for all the info, very helpful.

I'm hoping to use my existing Atomic universal swivel hose. I assume this hose doesn't have an OPV built-in?

Also, how do I go about adjusting the IP on the first stage?

 

[tbone1004]

Thanks for all the info, very helpful.

I'm hoping to use my existing Atomic universal swivel hose. I assume this hose doesn't have an OPV built-in?

Also, how do I go about adjusting the IP on the first stage?

you'll need a hose adapter as stated above. Personally I think the best way to go with the cost of that swivel hose is to just invest in an omniswivel adapter that takes care of adapting to normal hose, opv, and ball swivel all in one. It's not cheap but I think it's about the same price as the Atomic hose.

IP adjustment on that first stage needs to be done by a technician since it has to be taken apart to do it. You'll also need someone who is familiar with the Xstream as that will need to be tuned directly to the Atomic first stage since it is an unbalanced second