What's the most popular tank size?

[Scuba Duba Doo]

I'm 6'2, 180 and dive a HP steel 120 as single rig or double HP steel 120's. No problem with either but prefer my horizontal control with the doubles. The single 120 has lateral stabilaty issues due to the high negative weight at the start of the dive (-14 lbs FW). It gets better as you consume the air.

 

[LobstaMan]

IMHO...go with the HP100s. Unless you are over 6' you'd probably be more comfortable w/ the 100s than the 120s. Most of the divers in the NE using 120s or larger are big guys. But, I have never used a 120, so you might want to try one first.

Forget the AL80s and steel 72s unless you're just doing shallow shore stuff. I've used the 100s for both dry suit and wet suit diving here in NE and couldn't be happier with the size, bouyancy, trim, gas volume, etc. Never come up with less then 800. Unless you're doing a 50fsw nitrox dive, I doubt you'll ever run out of air before your NDLs arrive. Good luck.

LobstaMan

 

[CompuDude]

IMHO...go with the HP100s. Unless you are over 6' you'd probably be more comfortable w/ the 100s than the 120s. Most of the divers in the NE using 120s or larger are big guys. But, I have never used a 120, so you might want to try one first.

Forget the AL80s and steel 72s unless you're just doing shallow shore stuff. I've used the 100s for both dry suit and wet suit diving here in NE and couldn't be happier with the size, bouyancy, trim, gas volume, etc. Never come up with less then 800. Unless you're doing a 50fsw nitrox dive, I doubt you'll ever run out of air before your NDLs arrive. Good luck.

LobstaMan

The OP stated in post 1 that he is 6' tall, 215#.

He would probably do ok with an HP120, but I'd recommend the shorter HP119 instead. Only 1 cf difference, but it's the same height as an HP100 (also an excellent choice, of course), but it's an 8" tank instead of 7.25" diameter. HP120s are just beastly long. I dive a mix of HP100s and HP119s pretty much exclusively, unless I'm traveling and stuck with Al80 rentals.

But I agree that for 90+% of the diving population, the HP100 is the best all-around tank out there.

 

[xwhitesmokex]

I"m wondering with new tank technology, what do the "experienced" think about the new E and X series... particularly the E-9-119 and the X8-119's

also, would a .75 per tank Outer diameter make a big difference when having doubles?

my .2 cents (which are not worth much) is it's always nice to have your own equipment.. you know where it's been!!
but as a penny pincher you have to weigh the cost of the tank, cost of maintenance and inspection with the cost of renting and how many dives you do.

From reading, i'd stick to HP steel tanks .. eventually they will be more cost effective.

 

[CompuDude]

I"m wondering with new tank technology, what do the "experienced" think about the new E and X series... particularly the E-9-119 and the X8-119's

also, would a .75 per tank Outer diameter make a big difference when having doubles?

my .2 cents (which are not worth much) is it's always nice to have your own equipment.. you know where it's been!!
but as a penny pincher you have to weigh the cost of the tank, cost of maintenance and inspection with the cost of renting and how many dives you do.

From reading, i'd stick to HP steel tanks .. eventually they will be more cost effective.

The E series tanks were made by PST, which has been out of business for about a year. The X series are made by Worthington, and are a solid replacement.

The E7 and E8 tanks are 7.25" diameter (same as aluminum 80s) and 8.0" diameter, respectively. Same scheme for the X7 and X8 series tanks. I've never heard of an E-9 tank.

8" tanks are pretty big when you're doing doubles, but enough people do them (especially with larger capacity LP tanks) all the time, so it can't be that bad. I intend to stick to doubled Al.80s and HP100s, personally.

 

[xwhitesmokex]

thanks Dude, and that 9 was a typo.. i meant 7

I just went to their website and they don't seem to be out of business anytime soon.. http://www.pstscuba.com/

know anyone selling them less than $325.. i really like the compact size they come in ...

 

[CompuDude]

thanks Dude, and that 9 was a typo.. i meant 7

I just went to their website and they don't seem to be out of business anytime soon.. http://www.pstscuba.com/

know anyone selling them less than $325.. i really like the compact size they come in ...

Don't believe everything you read online.

PST is dead and gone, although there are rumors an off-shore company is trying to buy their stuff so they can take advantage of their good name.

There is a VERY small amount of new tanks left in the retail channel, but PST hasn't made any tanks since early 2006, unless I'm mistaken. Lots of threads about PST's status in the tank forum, a quick search will show you I'm not wrong.

 

[GLENFWB]

IMHO...go with the HP100s.

Haven't seen anyone recommend the LP 108...is there a reason why everyone is steering clear of the LP tanks? I know the HP gives you the less size/weight issue, is that the main reason why most are recommending the HP? My LDS told me to avoid the HP because of the "getting full fills" issue.

 

[CompuDude]

Haven't seen anyone recommend the LP 108...is there a reason why everyone is steering clear of the LP tanks? I know the HP gives you the less size/weight issue, is that the main reason why most are recommending the HP? My LDS told me to avoid the HP because of the "getting full fills" issue.

LP tanks are big and heavy. The HP100 is a win, simply because compared to an Al.80, it's smaller (several inches shorter), lighter (about a pound lighter, depending on the manufacturers you are comparing), and you'll still ALWAYS have more gas at any given pressure.

3000psi in an Al.80 (a pressure you should never have a problem reaching) gives you 77.4 cf of gas. That same 3000 psi in an HP100 gives you 87 cf of gas... 10cf and more than 10% more.

At 3200 psi, you're putting you Al.80 at serious risk... few shops will overfill an Al. tank, and it's simply not a good idea to do so. But that 3200 is no big deal for your HP tank, and you now have 93 cf of gas: quite a bit more than the Al. can take. Most shops can pump 3300-3400 psi (giving you 96-99cf), it's hitting the truly full level of 3442-3500 that they start having issues (not all shops, just those with underpowered compressors).

Some shops don't like HP tanks because reaching those high pressures is harder on their compressors. That's self-interest, though... it doesn't mean HP is bad, it means the shop owner just doesn't like them for selfish reasons.

Sure, you can overfill LP tanks. But that's risking your tank (not to mention liability issues for the shops that do it). I'd rather underfill an HP tank than overfill an LP tank. And with the HP tank, I have a smaller, lighter package to carry around.

 

[in_cavediver]

At 3200 psi, you're putting you Al.80 at serious risk... few shops will overfill an Al. tank, and it's simply not a good idea to do so. But that 3200 is no big deal for your HP tank, and you now have 93 cf of gas: quite a bit more than the Al. can take. Most shops can pump 3300-3400 psi (giving you 96-99cf), it's hitting the truly full level of 3442-3500 that they start having issues (not all shops, just those with underpowered compressors).

That 3200 psi in the al80 isn't really an issue. Many of the shops I've been to give a hot 3200 in AL tanks which cools to 2900-3100. Its not until you go into the gross overfill category (3400+ or so) that you have real issues. *MAJOR DISCLAIMER*. I do not advocate overfilling AL tanks. The better method is to do a hot 3000, let it cool and top off to 3000 again.

Sure, you can overfill LP tanks. But that's risking your tank (not to mention liability issues for the shops that do it). I'd rather underfill an HP tank than overfill an LP tank. And with the HP tank, I have a smaller, lighter package to carry around.

There is a long history of overfilling some LP steel tanks with generally good results (few failed hydros etc). That said, overfilling does reduce tank life. In this day an age, if you can get basically the same tank as HP as LP (true for many LP tanks), the HP is the better choice. There are LP tanks out there that do not have a HP equivalent and in those cases, LP is your only choice.