One other possible factor that hasn't yet been mentioned: the larger 8" diameter HP130 you'll find often doesn't fit in the sockets many charter boats have for tanks. They're often set to accommodate the 7.25" diameter typical for AL80's, which also fits the steel HP100's.
If you are tall or have a long torso, you might also consider the steel HP120's, which have nearly the same amount of gas as the 130 but in the more standard 7.25" diameter. According to this chart, I believe the X7-120 is also the most efficient tank anywhere in terms of rated cubic feet of gas per pound of dry weight (3.16cf per pound), even compared to aluminums.
On the other hand, on some boats not only are the cylinder wells sized for the narrower tanks, but they don't even accommodate the boots on a typical 7.25" steel tank! To me this is a horrible oversight, but it happens...
>*< Fritz
P.S. If you just want to go for broke and have enough gas to do tank fills for other divers while underwater, get a steel 150! One hoss of a tank, but I've been seeing a few in use lately.
If you are tall or have a long torso, you might also consider the steel HP120's, which have nearly the same amount of gas as the 130 but in the more standard 7.25" diameter. According to this chart, I believe the X7-120 is also the most efficient tank anywhere in terms of rated cubic feet of gas per pound of dry weight (3.16cf per pound), even compared to aluminums.
On the other hand, on some boats not only are the cylinder wells sized for the narrower tanks, but they don't even accommodate the boots on a typical 7.25" steel tank! To me this is a horrible oversight, but it happens...
>*< Fritz
P.S. If you just want to go for broke and have enough gas to do tank fills for other divers while underwater, get a steel 150! One hoss of a tank, but I've been seeing a few in use lately.
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