HP 100 or 120

[livetwodive]

I currently have four AL80's for my wife and I. Till now that has been sufficient for us plus it was the best option compared with steel 72's when we started diving. Now that we are diving Nitrox more gas would be a good thing for our bottom time. Also, my son started diving and a couple more tanks are needed.

I'm soliciting some opinions about overall size. The HP100 sounds like a popular tank and would be better for buoyancy but subscribing to the more is better I was looking at the Worthington X7-120 for her and I for at least our primary "deep" cylinder. I was thinking the X7 because it would have the same diameter as our AL80's which will make switching tanks easier. From what I see, while the tank is heavier the lead we won't need to counteract the AL80 will result in roughly the same weight on our back. The only thing we'll need to remember is to add 4-5 lbs of lead when we switch tanks between dives.

What are you experiences when switching from the AL80 to steel? Is this strategy workable? I don't see me buying a full set of steel tanks. I'll be lucky if I get to buy two after what I've spent on gear upgrades for us this year.

 

[weaserm99]

If switching between the aluminum 80 and the HP 100 then the weight difference will be about 4-5 lbs. If going between the AL 80 and the HP120 then the weight difference will be much more. The other thing to consider is that the HP120 is longer than the other tanks. Ive used both of the tanks and find that they both work well and choosing between the two depends on the situation.

 

[ScubaSteve]

I have two steel 120's and an AL80. I love my 120's and dive them deep, shallow. have I found 6 pounds was the best number to add going from the 120 steel to an AL80 but find your own number with whatever you get. Personally I think that if you buy the HP steel tanks, you will stop diving the AL80's.

 

[dannobee]

One more element to add. HP100's are about the same height as your AL80's. The HP120's are about 3" taller. Unless you're really tall, it's awkward to carry them. You can't just let your arm hang, it has to be at an oddball angle to keep it from dragging on the floor.

I use one HP120 for So Cal boat diving (and have to carry it up and down the ramp once). For all my other diving, it's HP100's for singles.

Another thing, if you're in FL and wear little or no weight with your AL80, you might be uncomfortably negative with a steel tank.

 

[FritzCat66]

I'm soliciting some opinions about overall size. The HP100 sounds like a popular tank and would be better for buoyancy but subscribing to the more is better I was looking at the Worthington X7-120 for her and I for at least our primary "deep" cylinder. I was thinking the X7 because it would have the same diameter as our AL80's which will make switching tanks easier.

Both are good tanks. The 100 has about the same dimensions as an AL80 and seems to make for the easiest transition. The 120's are the largest-volume tank available in 7.25" diameter, but are also some of the longest tanks on the market and not for everyone.

I ultimately went with the 120's, but that's because I have the torso of a six-footer (although my short legs make me only 5'10"). But I'm the only one who dives my tanks. If you're planning on sharing, the 100's will fit more divers. If not, having 150% the capacity of your old AL80's on your back in addition to losing so much lead is awfully nice!

Especially with those convertible valves, either model Worthington is a good investment that will last probably your entire diving lifetime, and still hold their resale value pretty well if kept clean, VIP'd, and hydro'd.

 

[Scott L]

I'm soliciting some opinions about overall size. The HP100 sounds like a popular tank and would be better for buoyancy but subscribing to the more is better I was looking at the Worthington X7-120 for her and I for at least our primary "deep" cylinder. I was thinking the X7 because it would have the same diameter as our AL80's which will make switching tanks easier. From what I see, while the tank is heavier the lead we won't need to counteract the AL80 will result in roughly the same weight on our back. The only thing we'll need to remember is to add 4-5 lbs of lead when we switch tanks between dives.

What are you experiences when switching from the AL80 to steel? Is this strategy workable? I don't see me buying a full set of steel tanks. I'll be lucky if I get to buy two after what I've spent on gear upgrades for us this year.

I believe the HP100 would be the best selection by far. Even with a mediocre SAC rate your limiting factor at depth will be NDL with the 100's. The Worthington X7-120 works well for taller divers but at 29.3" tall I am betting your wife will not like...

 

[livetwodive]

Personally I think that if you buy the HP steel tanks, you will stop diving the AL80's.

That was my thought and is the grand plan in the back of my mind. I like owning two tanks for each diver in the family (now 3!)for the typical two tank boat dives. If I get two HP tanks now my wife and I will have the same size tank for each dive. I might get another pair of HP tanks in a year or two. Until then I'm stuck with the AL80 for the second (typically shallower) dive.

We are driving distance from the Keys (about 5 hours to Key Largo) so I like taking my own tanks. Tomorrow we head for West Palm and plan on a few Beach dives and at least one two tank boat dive.

This was all so much simpler when I started diving in the 80's. Nobody argued about fins, you bought what was on the wall. Tanks...pick from the AL80 or Steel72, that seemed obvious (again more=better) so the biggest decision was which color. I was out of diving for a few years and the choices exploded. My Ranger is still a great BC but now BP/W is the way to go...or so I hear from one or two posters. Then everyone was happy to go diving and not come back bent diving the Navy tables using air... now we are supposed to "Do It Right"

Anyway I'm just happy to enjoy diving, thanks.

 

[mksmith713]

My wife is 7 inches shorter, 100 pounds lighter and her SAC is muuuuuuch lower than mine.
She has these cute little sawed off steel 72's.
I dive big hulking @ss steel 120's.
We burn through our gas at about the same time.
Neither of us need any added weight.

 

[skynscuba]

If your BC fails, and you aren't wearing much of a suit, you will not have enough dumpable weight to float.

 

[Scott L]

If your BC fails, and you aren't wearing much of a suit, you will not have enough dumpable weight to float.

There is always the option of purging-off excess gas with the octo in order to ascend more quickly...