AL 80 as a pony

[mick allein III]

I dove a slung 80 for practice yesterday and it went very well. Initially a little heavy but when I breathed it down to 2200, the bottom got floaty and tucked nicely on the side. More drag than the 40, but all in all very dive able. Thanks for your help

 

[Barnaby'sDad]

I backmount a HP100 and sidemount an AL 80 frequently. 1+ for the posts above. Make sure to ballast for the gas you use. The thing I like about it besides a good source of redundant gas is that I can use more of the fill than diving a single tank. The other day I dove for 100 minutes using both tanks. The next dive I kept the HP100 with 1900 left and sidemounted a fresh AL80. I would have never started a dive with just the 1900 left in the HP100. Used most of that up with enough left in the AL80 for its use the next day.

To keep my redundancy options fully open I swap which tank I'm breathing from every 500 psi. That is not for trim, but to keep some gas in each tank.

Most of my diving is shore based. 2 sidemounts take more effort for me than having one on my back and clipping the other on after getting in the water.

I currently backmount a HP100 and I'm leaning toward putting together a redundant air supply.

I still have two AL80's that I started out with. Rather than buy another aluminum tank (AL40), I'm leaning towards rigging up one of my AL80's to sling for deep or the occasional solo dive.

I got them O2 cleaned/certified not too long ago and they have four years remaining on the hydros, so it makes sense to repurpose one of them and keep using it. (If money was not an object..I'd just put together a sidemount setup with them, but I'm not ready to do that at this point).

Assuming a standard AL80 (Catalina...so -1 full and +4 around 500 PSI)...if I alternate usage during a dive (ex. Every 500 PSI) and I don't run the AL80 below 1,000 PSI...how much weight would I need to add to run this tank configuration? 2-3 lbs?

Yes...bumping an old thread, but it's a relevant conversation to pick up and run with. Thanks in advance.

 

[tbone1004]

@Barnaby'sDad you typically do not add weight to compensate for a pony bottle. The AL80's are not particularly positively buoyant, especially catalinas once a regulator is on them. I would not recommend adding weight to compensate.

 

[Barnaby'sDad]

@Barnaby'sDad you typically do not add weight to compensate for a pony bottle. The AL80's are not particularly positively buoyant, especially catalinas once a regulator is on them. I would not recommend adding weight to compensate.

I did not add weight for the AL40 that I got to sling and try out recently. I wasn't sure if that would change for an AL80. Thank you.