• Welcome to ScubaBoard


  1. Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

    Benefits of registering include

    • Ability to post and comment on topics and discussions.
    • A Free photo gallery to share your dive photos with the world.
    • You can make this box go away

    Joining is quick and easy. Login or Register now by clicking on the button

Pony tank

Discussion in 'Tanks, Valves & Bands' started by Karriff karim, Jan 23, 2021.

  1. Karriff karim

    Karriff karim Registered

    # of Dives: 25 - 49
    Location: Fort Lauderdale, Florida
    53
    21
    I’ve been doing a lot of deep dives in the past few months and I always start my accent at 1000 psi like you should and in turn I exit the water with around 600 to 700 psi. I’m looking into pony tank options. Ones with the all in one reg, second screwed right into the first stage that’s hand held if needed. then there is the ones that you basically mount your pony to your primary tank with a hose from the first stage to the second. What do you guys think. So does this mean I can get rid of my Octo to my primary tank. Can I also see setups on how it’s mounted. I’m currently using a jacket bcd but I am planning on going backplate soon.
     
  2. Searcaigh

    Searcaigh Chromodoris gordonii Staff Member ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Dubai, UAE
    6,462
    5,401
    Lots of threads on this subject.

    I would recommend a 30-40 cu ft pony depending on your SAC rate with an additional first and second stage, plus SPG.

    You can use it with a jacket BCD provided you have suitable stainless steel D rings in the correct place.

    And yes you can remove your octopus from your main first stage, however that means you must always dive with your pony in order to be a good buddy.
     
    Compressor and Karriff karim like this.
  3. Karriff karim

    Karriff karim Registered

    # of Dives: 25 - 49
    Location: Fort Lauderdale, Florida
    53
    21
    I typed in pony tank or pony bottle in the search bar and nothing came up. I was thinking of doing a 19 cu ft, I literally did not think about when I’m not using a pony. That’s probably why a lot of people like to use the air source inflator Octo combo which I just removed from my regs.
     
    Searcaigh likes this.
  4. gqllc007

    gqllc007 ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 100 - 199
    Location: Albany NY
    240
    99
    Karriff karim likes this.
  5. Karriff karim

    Karriff karim Registered

    # of Dives: 25 - 49
    Location: Fort Lauderdale, Florida
    53
    21
  6. Searcaigh

    Searcaigh Chromodoris gordonii Staff Member ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Dubai, UAE
    6,462
    5,401
    This may work for you, but at some point you might consider tech or advanced decompression and a 30 or 40 cu ft is a better choice.
     
    grantctobin likes this.
  7. Silt Life

    Silt Life Regular of the Pub

    # of Dives: 25 - 49
    Location: Hotlanta
    98
    156
    Solo Divers is Sub forum of Advanced Scuba Discussion and has plenty info.....
     
  8. VikingDives

    VikingDives Mostly Harmless ScubaBoard Sponsor

    # of Dives: I'm a Fish!
    Location: New Mexico
    194
    126
    Spare air as a replacement for an octo? Not a good idea, to put it mildly.
    Getting rid of your octo because you have a (bigger) pony bottle? See above.

    A pony bottle's purpose is for times when the bovine excrement has hit the rotating oscillating blades. You should use it in addition to your standard gear, not as a replacement.

    Take some time to figure out what your SAC/RMV is, and you'll have an answer as to how much air you need. That will guide you regarding tank size.
     
    Colliam7 likes this.
  9. scubadada

    scubadada Diver Staff Member ScubaBoard Supporter

    # of Dives: 1,000 - 2,499
    Location: Philadelphia and Boynton Beach
    14,287
    10,681
    Hi @Karriff karim

    What are your deep dives, within rec limits, <130 feet, or deeper? I assume you are diving with a buddy and not solo, is that right? Your profile says you are OW and in line for AOW. Do you have future plans for your diving? What is the purpose/are the purposes of you having a pony now?

    I do most of my diving solo but more than occasionally dive with others. I have always left my 2nd attached, I happen to use a primary on a 40" hose and my 2nd bungeed on a short hose. The all in one, Spare Air, is generally too small to serve as an all purpose pony. Larger cylinders are generally either back mounted or slung. I choose to sling my pony.

    For solo diving, a common calculation for pony size is to ensure that you would have the gas needed to ascend on any dive you make. A very conservative calculation would be to spend a minute at depth, make a normal ascent with a 3 min safety stop, at twice your average RMV. Of course, in an emergency, you could ascend at faster rate, and, on a no stop dive, you could safely skip the safety stop. If you know your RMV, you can make that calculation now. If not, you might want to spend the time determining your gas consumption.
     
    JimBlay and James79 like this.
  10. gamon

    gamon Regular of the Pub

    # of Dives: 200 - 499
    Location: US
    125
    88
    I started with a Spare AIr maybe 10-15 years ago, then upgraded to a 19cf pony bottle and now I carry a 30 ct pony bottle.

    You say that you always start your ascent with 1000 psi. When carrying a pony bottle I cut my main tank reserves roughly in half, so I'll start to ascend at around 600 psi and maybe have 300 at my safety stop and surface with 50-100 psi.

    I've got the reserve in the pony tank so it allows me to draw my main tank gas lower, giving me extra gas on virtually every dive plus the safety of the redundancy of the second independent tank and regulator.

    I have an integrated octo regulator as well, because on shallow reef dives I don't typically bother with the pony tank.
     

Share This Page