I'm debating between these two choices for a backmount pony mounted on the right side of the main tank upside down with a left mount valve and 40" hose run under the right arm. Main gas is HP100. Diving 90' or less in all cases.
The steel 23 would provide a bit more air than the 19, but be slightly more negatively buoyant at -2.64 full and -0.66 empty. I would most likely counter this with 2lb trim weight on the left shoulder strap to counter potential rolling to the right.
The aluminum 19 is a bit shorter height wise (2" shorter) and more buoyant at -1.7 full and -0.3 empty. Not significant, but something to consider.
Land weight is irrelevant, as I'll be loading these from my truck straight to the boat.
I'm leaning to the steel HP 23.
The steel 23 would provide a bit more air than the 19, but be slightly more negatively buoyant at -2.64 full and -0.66 empty. I would most likely counter this with 2lb trim weight on the left shoulder strap to counter potential rolling to the right.
The aluminum 19 is a bit shorter height wise (2" shorter) and more buoyant at -1.7 full and -0.3 empty. Not significant, but something to consider.
Land weight is irrelevant, as I'll be loading these from my truck straight to the boat.
I'm leaning to the steel HP 23.