Better SAC rate switching from Poseidon Xstream to Apeks

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Hi Tbone, im a newbie and i using a poseidon xstream. I realized that by sipping it, which my instructor recomended, did not give me any air, it has to be an effort to inhale the air from the 2nd stage. Would you share some tips on how to breathe efficiently on it? Does the 4secs inhale and 4secs exhale still works. I did that and my sac level is 2 bar 🫣

You should be able to "sip" on an Xstream, it may not be ideal for that style of second stage but it should certainly deliver air. You should have a Poseidon tech look at it and adjust it as necessary, it is critical that you find a certified Poseidon tech to do it though because they are so different from the other regulators out there.

As far as the 4secs bit, I don't believe in having anyone subscribe to a certain breathing pattern. You need to breathe however your body is comfortable breathing. If you're a musician or a swimmer that may be a rapid inhale with a long exhale, if you're a runner it may be more balanced. What is important is that you are breathing naturally and comfortably. Size of breath should also be natural, similar to the size of your breath while taking a leisurely walk on the beach or down the street. You'll learn over time that breathing and buoyancy control are very intimately intertwined and will start to adjust the size and frequency of your breathing pattern for buoyancy control but you should not think about it as "deep" breaths or think about seconds of inhale exhale. The only part that you have to be very cognizant of is making sure you make a full and complete exhale so you don't build up CO2
 
Perhaps with a brief pause prior to exhalation
whatever feels natural. I've found that when students concentrate too much on breathing a lot of other stuff goes seriously sideways so I try to have them find their natural breathing pattern first and then once they're comfortable we work on how that affects buoyancy and some things to start thinking about.
 
Hi Tbone, im a newbie and i using a poseidon xstream. I realized that by sipping it, which my instructor recomended, did not give me any air, it has to be an effort to inhale the air from the 2nd stage. Would you share some tips on how to breathe efficiently on it? Does the 4secs inhale and 4secs exhale still works. I did that and my sac level is 2 bar 🫣

I use a Mares reg which pairs an unbalanced second with a balanced first. There's no way to "sip" on the inhale, once the second opens you get a strong flow. However, you can take as long as you want on the exhale. I kind of dribble out the air over 10-20 seconds normally.

You can adopt this pattern with a little practice. A compressed version of this is what I used to do as a competitive swimmer (really fast inhales and relatively long exhales underwater) and, as someone pointed out above, this is how brass and woodwind musicians breathe. I think opera singers too.
 
Perhaps with a brief pause prior to exhalation
I was a competitive swimmer from the age of 4. I was certified when I was 16. It was obvious from the start that my gas consumption was better than my peers and many professionals. I paid no particular attention to my breathing.

It was not until years later that I paid attention to my diving breathing pattern. It was a relatively rapid inhale, a brief pause, a slow exhale, followed by another inhale. Turns out this is the opposite of the normal breathing pattern on land. The diving breathing pattern came completely naturally to me.

I'm now a 70 year old man with 2350 dives. My average RMV over the last almost 1900 dives is 0.36 cu ft/min over a very wide variety of circumstances. The breathing pattern works for me, it's my impression that it is associated with very good gas exchange.

Good diving to all
 
Over the past year I have moved away from diving my Xstream regs and switched to the ATX 50's (diving sidemount). My last cave week in Mexico I noticed a considerable difference in SAC rate. With my Poseidon's', I was getting an average of 19-20psi/min.
I have to agree with a few others, in that its is most likely just an adjustment issue, since my Xstream regulators require no effort to breathe; are set "hot," just short of free-flow, and can easily be "sipped."

This related topic has appeared a few times over recent years, especially in the DIY forum, but here is a note from the service manual, once again:

"Some divers like the setting extremely light, and some prefer a higher cracking pressure. Ask your customer. Technically, Xstream can be adjusted from 0 mm w.c to > 100 mm w.c. The risk for a free flow increases with decreasing cracking pressure. Below 25 mm w.c in a certain attitude (exhalation diaphragm the shallowest and inhalation diaphragm the deepest), the regulator inhalation valve will stay permanently open, bubbling. Above 40 mm w.c the breathing [is an effort] . . ."
 
Thank you for all the feedbacks, i happened to buy the reg from authorized poseidon dealer here, but have not tuned it to my preferences, i will pay them a visit and ask for help. Im glad to be part of this forum, i find it resourceful when seasoned divers sharing thoughts here. 🙏
 
Thank you for all the feedbacks, i happened to buy the reg from authorized poseidon dealer here, but have not tuned it to my preferences, i will pay them a visit and ask for help. Im glad to be part of this forum, i find it resourceful when seasoned divers sharing thoughts here. 🙏
don't take this the wrong way, but at this point in your diving you don't really have any "preference" for how they are supposed to be tuned since it is highly possible that you have never actually breathed on them when tuned to factory spec if they ever gave you a situation where they didn't crack. The Xstream has one of the lowest breathing efforts of any regulator on the market and is capable of a cracking effort that is lower than I'm pretty sure everything except its Jetstream older brother and a double hose. It sounds like they may just need to be adjusted back to factory specs and then you should take them for another spin and stop focusing on trying to breathe a certain way and see how you like them.
 
don't take this the wrong way, but at this point in your diving you don't really have any "preference" for how they are supposed to be tuned since it is highly possible that you have never actually breathed on them when tuned to factory spec if they ever gave you a situation where they didn't crack. The Xstream has one of the lowest breathing efforts of any regulator on the market and is capable of a cracking effort that is lower than I'm pretty sure everything except its Jetstream older brother and a double hose. It sounds like they may just need to be adjusted back to factory specs and then you should take them for another spin and stop focusing on trying to breathe a certain way and see how you like them.
Yes that might be true, will check the setting if its accordance to the factory setting. I tried apeks from my instructor, it does not need that extra effort as to compare to the xstream. The regulator should be out of the box purchase, will be suspicious if its not set to a factory setting. Thank you for the suggestion. 🙏
 
Yes that might be true, will check the setting if its accordance to the factory setting. I tried apeks from my instructor, it does not need that extra effort as to compare to the xstream. The regulator should be out of the box purchase, will be suspicious if its not set to a factory setting. Thank you for the suggestion. 🙏
the Xstream is an unbalanced valve design, it needs to be matched to the first stage it is attached to which should be done by the shop when you purchase it. All regulators should be done like that, but especially Poseidons
 
https://www.shearwater.com/products/perdix-ai/

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