Faber HP 23

[Basking Ridge Diver]

Right, but also lets say you were doing a weekend of diving which included 3-4 repetive dives each day. Every dive you may lose gas from the pony, assuming you dive with the tank on. So whether it's when you first splash, pressurize/depressurize the reg, a slight free flow here and there, you could end up having a situation where your pony has a lot less gas than you planned toward the latter dives. A tip I learned on here from others is to pick up a transfer whip ($100) DGX Gas Transfill Hose with Analog Gauge | Dive Gear Express® . Then you can top off your pony as needed with other tanks. But, if your other tanks aren't high pressure tanks there's no way to transfer the gas to your high pressure pony to equalize and have a full pony. Did I explain that well enough?

This may not be a concern depending on your type of diving, but I felt it was worth mentioning.

I would have said it slightly different - the source tank (your large tank or back gas) if it is a low pressure tank LP85 and is only filled to 2400 PSI would not fill your target tank HP19 (your pony) because it is say 2800 PSI is at 18 cu feet due to some leakage.
Therefore when you go to use your transfill whip you will get this.. LP85 has 2473 PSI and 88 cu feet while your pony HP 19 would have 2473 PSI and 16 cu feet. Both tanks will equalize to the lowest pressure so you really are not filling your pony you are filling your back gas...

If you are using HP or LP tanks it could be a consideration to keep in mind - I use LP Back gas but I bump them up. Since I fill my own tanks filling a pony is never an issue for me.

 

[2airishuman]

I recently bought an AL19 for a pony tank after having considered an FX23.

The full AL19 with valve and regulator is slightly negative in fresh water. The FX23 would be markedly negative. I decided that I would prefer the AL19 because it would have minimal effect on overall buoyancy and trim. Since I sling the pony and want the option of clipping it on after entering the water, I was also concerned that it would be easier to lose the FX23 if a mistake were made while trying to secure it, as it would sink rapidly.

Finally, it is my experience that it is more difficult to get a good fill for 3442 PSI cylinders than for 3000 PSI cylinders, so the 4 cf advantage could turn out to be somewhat illusory.

An advantage of carrying the pony cylinder slung is that I can switch to a larger cylinder for a particular dive if circumstances warrant. 19cf is sufficient for most of what I plan to do. I have a 40cf I can pull out if I really need it.

Finally, a fact to consider is that if you ever want to back-mount the pony, some of the best mounting brackets are not available in a size that will fit the FX-23.

 

[WatchTryst]

I would have said it slightly different - the source tank (your large tank or back gas) if it is a low pressure tank LP85 and is only filled to 2400 PSI would not fill your target tank HP19 (your pony) because it is say 2800 PSI is at 18 cu feet due to some leakage.
Therefore when you go to use your transfill whip you will get this.. LP85 has 2473 PSI and 88 cu feet while your pony HP 19 would have 2473 PSI and 16 cu feet. Both tanks will equalize to the lowest pressure so you really are not filling your pony you are filling your back gas...

If you are using HP or LP tanks it could be a consideration to keep in mind - I use LP Back gas but I bump them up. Since I fill my own tanks filling a pony is never an issue for me.

This may have been discussed in other threads, however, I wanted to ask anyways. Do you have your own compressor/fill station at home?

 

[Basking Ridge Diver]

This may have been discussed in other threads, however, I wanted to ask anyways. Do you have your own compressor/fill station at home?

Yes but it is at the firehouse - I am a volunteer firefighter. We use six 6000 PSI bottles of banked air and we have a compressor. We do not have a dive team but it is very convenient so that on a moments notice I can dive.

 

[WatchTryst]

Yes but it is at the firehouse - I am a volunteer firefighter. We use six 6000 PSI bottles of banked air and we have a compressor. We do not have a dive team but it is very convenient so that on a moments notice I can dive.

That is an awesome perk for your voluntary duties!