HP steel 120 or 130?

[donooo]

Just going to throw this out there -- doubles aren't always the immediate answer. Personally I feel they're pushed a bit too much on people who probably don't have the experience needed to start diving them. Kind of a "too far too fast" thing...

100%, figure out why you are using the air and try and work on the skill. Bigger is not always better.

On an aside watched two guys doing a normal recreational dive a few days a ago with doubles. Lot of junk to haul up and down the beach and off to refill for an AL 80 dive.

don O

 

[WOODMAN]

Then we have the issue of traveling divers who need big tanks on vacation trips, like me. Getting just a 100cf tank on a trip can be real fun, although some places are coming around to this now. Cozumel has several operators who stock the 120 tanks now, for example. I prefer liveaboards, and this can often prove a real problem. I have used a couple of operators in south florida, and have managed to rent a 130 hp tank in Miami and schlep it around to the boats as needed. So far the boats have welcomed this little ploy, but the hassel involved is starting to get old (and expensive! ) Too bad that it is a worse hassel to buy and ship a tank back and forth. When you need the extra gas when you travel, the options are few. And god help you if you go anywhere remotely exotic! Beeg tanks? No comprende, senor.

 

[nereas]

Twin 72s aren't exactly a viable option if you're looking to do TWO dives...

I have 2 sets of twin 72s for that very reason. These are perfect for diving in the range of 100 to 150 fsw.

Just as I have 2 sets of twin 130s for deeper diving.

I believe you are trying to adapt a large single tank for depths that warrant smaller twin tanks instead.

If you want to dive single tanks, I think you should keep your depth shallower than 100 fsw.

And if you want to dive 100 fsw or deeper than 100 fsw, I believe the best solution is twin tanks.

 

[Rainer]

I have 2 sets of twin 72s for that very reason. These are perfect for diving in the range of 100 to 150 fsw.

Just as I have 2 sets of twin 130s for deeper diving.

I believe you are trying to adapt a large single tank for depths that warrant smaller twin tanks instead.

If you want to dive single tanks, I think you should keep your depth shallower than 100 fsw.

And if you want to dive 100 fsw or deeper than 100 fsw, I believe the best solution is twin tanks.

Listen, I also take doubles below 100'. That said, a single set of 72s is not at all viable for those of us living where boats won't let you take on two sets of doubles and you plan to do two dives. In that case, either bring bigger doubles, or start diving enough so that your SCR falls to where a 100cf cylinder is ok for a 100' dive (I certainly know it's fine for me!).

 

[Colliam7]

Going from HP 100s to HP120's you will add about 5 lbs in empty weight, about 9 pounds in full weight, but a whole 4 inches in tank length. That may be an issue. Going to the 130s, you have a bigger diameter (8" vs 7.25), but only 2 additional inches of length. However, you add 10 lbs empty weight and ~14 lbs full. If you are OK with the extra weight, why not go with the 130? One other option would be a HP 119, with which you would have a fatter tank (8") of about the same length as your 100, with weight gains of 8 and 11 lbs empty and full.

For dives in the 100' range, a single 120 or 130 is nice (I dive 120s). You may hit NDL before you run low on gas, but who cares. Come on up with a little extra gas (which is a possible goal, as I read your post). Or, you simply may be able to stay down longer, still within NDL, than with a 100. Sure, work on your gas management as suggested. But, if I have a choice of having 30% more air, and the extra weight is not a problem, I am going to take it. The doubles suggestions are good, but a larger single is a cheaper, and easier, option. I dive double 120s as well, and doubles are manageable. But, an easy rec dive to 100' or 115' with a big single is more relaxing. Taking along a pony - 19 cf or larger - is an interesting suggestion as well. Of course, then you have the expense of the tank AND a reg, and the expense of the fill on a second tank. I dive a 40cf pony with a single 120 at times, don't even notice the bottle is there, usually hit NDL with plenty of backgas, so the pony is a contingency bottle. But, it is worth thinking about.

 

[Tim Greaves]

I was thinking the same thing.. I deceided to get 130's which I will probably double up.. The HP tanks arent all that heavy and right now im using double LP steel 95's which are compareable to the HP130 in weight..

 

[nereas]

Listen, I also take doubles below 100'. That said, a single set of 72s is not at all viable for those of us living where boats won't let you take on two sets of doubles and you plan to do two dives. In that case, either bring bigger doubles, or start diving enough so that your SCR falls to where a 100cf cylinder is ok for a 100' dive (I certainly know it's fine for me!).

Yes, twin 130s work great for 2 dives in the range of 100 fsw to 150 fsw, I agree. I too have done this for boat diving to these depths. Dragging around one set of doubles beats two sets of doubles anytime.

 

[nereas]

I was thinking the same thing.. I deceided to get 130's which I will probably double up.. The HP tanks arent all that heavy and right now im using double LP steel 95's which are compareable to the HP130 in weight..

In terms of tank size and weight, the only LPs that I like are LP 72s. This is mostly because HP 80s are too short. For all other applications, I much prefer the HPs (HP 100s, HP 120s, and HP 130s).

 

[CompuDude]

In terms of tank size and weight, the only LPs that I like are LP 72s. This is mostly because HP 80s are too short. For all other applications, I much prefer the HPs (HP 100s, HP 120s, and HP 130s).

I'm starting to get more and more interested in LP85's, however... check out their specs. Very similar size to HP100, but an inch bigger and 1lb less buoyant.

For the OP, bear in mind the tanks that are a step up from the HP100 get a LOT heavier... you add about 50% in weight for 20-30% more gas. It'll accomplish your goal, but they're a beat to carry around. I almost never use my hp119 on shore dives, tho I like it a lot of boat dives. Just too heavy.

The best advice you've been given here is just to dive more and work on improving your air consumption. You may find the HP100 is all you need.

 

[Rainer]

I dive double LP85s, and I think they're great cylinders to double up. First, as CD notes, they're about the same size as HP100s. That said, they're about half the cost! Second, if you can get even a bit more gas in them than service pressure, you're doing well (at 3000psi, they're 100s). Having LP doubles also makes transfilling (from HP cylinders) easier; ditto for PP mixing. I shore dive these doubles in MA with little issue. Given my team's SCRs, these are just fine for any two recreational dives. For tech, they're fine for any one dive in 160' or less. If the OP is struggling with 100s, however, these are likely too small unless he can consistently get over-fills.