LP or HP for doubles setup???

[Bowtie22]

I am getting ready to buy a set of doubles in the next few months. I am planning on using them in the future for trimix. I am looking considering LP95's and HP100's for my setup.

So I want some feedback on which ones and why..... Pro's and con's of each....


Thanks

 

[Jimmer]

HP's all the way. I just don't buy this overfill and/or easier to PP blend in LP tanks crap.

 

[RAD Diver]

OK you will get lots of differing opinions on this, but the 95s are nice & that is what I used to have & for 1 dive they were fine. But the problem I had was if I did a 2nd dive I would have enough gas to do the dive, but if I were to lose my Deco gas for any # of reasons I would not have enough gas left to do complete Deco on back gas.
I now dive 108s & pumped (I know this will also start a war) I can carry enough. It doesn't sound like much of a difference, but every bit helps when it hits the fan.
HP tanks are fine, if you can get a full fill, but 100s would put you in the fine for 1 dive & not quite enough to do 2 properly. If you go HP I'd look at the 130s.

 

[TSandM]

LP95s are cheaper. HP100s are, I believe, lighter, but not by a whole lot. They trim out slightly differently. In cave country, you get a lot more gas in LP95s. That may or may not be relevant to the diving you intend to do.

 

[littlejohn]

From what I have read soon the steel tanks will come out with a LP, MP, HP ratings
So if you get a tank that is a 85 cf at 2600 it might be the same tank as a 100 cf at 3000 and still the same tank at 3442 but a 120 cf.
I have HP Steel in 80, 100, and 120 and the 100 is just about the best tank there is IMHO
You might look at the HP 119-cf its the same size as the 100-cf but it's a 8" tank.

Even if you get a hot fill and end up with only 3200 psi you still are diving twin 110's

 

[JBRES1]

I have a set of lp95's and like them very much.
I am thinking about making my 100's into doubles, but I really like how they trim out as singles.
Jim Breslin

 

[marchand]

If your LDS will overfill the LP tanks then I would get the LP tanks, but if they won't then I would definitely get the HP cylinders because they will be lighter.

 

[Scubakevdm]

I would get the tanks that balances my rig under the most common diving conditions the best.

 

[DA Aquamaster]

Not all LP 95's are created equal.

A Faber LP 95 weighs 37 lbs, is 8" in diameter is 24" high and holds 95 cu ft at 2640 psi.

A PST LP 95 weighs 44 lbs, is 8" in diameter is 25" high and holds 96.6 cu ft at 2640 psi.

In comparision a PST or Worthington E or X series 100 cu ft tank weighs 33 lbs, is 7.25" in diameter, 24" tall and holds 100 cu ft at 3442 psi. They are all about the same height, but the LP 95's are larger in diameter and 4 or 11 lbs heavier.

If you can get yur local dive shop to fill your LP 95 to 3500 psi, you will have 126 to cu ft of gas, which would give you a clear advantage over the lighter and smaller diameter 3442 psi E7-100.

On the other hand, if your LDS will not overfill your LP tank, you will get 5 more cubic feet and a lot less weight in the E7-100 or X7-100.

Alterantively you can compare the Lp 95 to the E and X series 120 and 130 cu ft tanks.

An E7-120 weighs 38 lbs is 28" tall, 7.25" in diameter and holds 120 cu ft at 3442 psi.

A PST E8-119 weighs 41 lbs, is 24" tall and 8" in diameter and holds 119 cu ft at 2442 psi.

And a PST E8-130 weighs 43 lbs, is 26" tall, 8" in diameter and holds 130 cu ft at 3442 psi.

At the same 3442 psi fill pressure an LP 95 holds 123 to 126 cu feet of gas. So in essence, the high pressure tanks only hold 3 or 6 cu ft less at the same 3442 psi fill pressure and weigh about the same or a few pounds less depending on the tanks being compared and the variety of tanks allows you to choose a shorter/taller/fatter/thinner tank depending on your trim needs.

And for only an inch or two more in height than an LP 95 and at the same basic 43 lb weight and 8" diamter as the PST LP 95, you can get the E8-130 with an honest 130 cu feet at 3442 psi.

So in short, if it were me and I were considering the LP 95, I'd either go with the E8-130 that could legally get 130 cu ft anywhere (instead of just in north Florida). If 200 cu ft were enough and I did not need 240 to 260 cu ft, I'd save 8 to 22 lbs per set of doubles and go with E7-100's.

That was what I chose to do as the 24" X7-100 trims very nicely and on those few occasions where more capacity is needed, an AL80 stage works nicely to give a total of 280 cu ft of bottom gas.

 

[Scared Silly]

To me there is more than just the fill. I had the choice between Faber HP 100 and LP 85's. I went with the LP85s. They were lighter and had better buoyancy characteristics (for my diving).