First time tank buyer

[passedoutwookie]

Will your local dive shop over fill cylinders for you? Most likely not… Get HP100s. They hold about the same amount of gas as a cave filled LP85 and have about the same dimensions.

Look for a pair of galvanized Faber, Worthington, or PST 100s.

 

[grantmac]

Faber FX100 is a fantastic SM tank if you can't get cave fills

 

[DiveGearExpress]

How to Select a SCUBA Tank | Dive Gear Express®

How to choose the best SCUBA tank for specific diving needs and styles of diving.

www.divegearexpress.com

 

[Jim Lapenta]

I am looking to purchase my own tanks for the first time. Looking for some advice from more experienced folks.

Buying two for side mount. Want DIN with left and right valve set up.

Would you recommend steel or aluminum? Is there a brand or model you love?

Thanks!

Steel LP85s. If you are just getting started and don't need large amounts of gas, get a set of LP72s. Often easy to find them super cheap compared to the others.
I know many people also like the HP100s for SM.

Most of the places I dived it was easier to get a 3000PSI fill on an LP cylinder than a good 3442 fill on an HP. Made those LP85s into 95s. Nice. You could get HP fills, but usually had to wait for them. One place required they be left overnight so they could be topped off in the morning to get a good fill.

AL80s are cheaper. That's about the only benefit to them for SM. Cold water? Not even worth considering. They are negative full and positive empty. Throws the weighting for cold water off. And when they get low the tails get very light. You need to have sliding D-rings on the waist belt or two sets so you can move them when they start to tilt ass up.
The LP72s will behave a little like the AL80s but not to the same degree of tilt. Still helps to have those sliding Ds or an extra set of Ds on the waist belt.

They're ok for warm water and caves in places like Mexico. In cold water, they are used for stages. Not primary cylinders.

I taught SM in cold water with 6 different rigs for close to 10 years before I retired. LP72s, LP85s, occasionally HP100s, and even LP95s were my primary cylinders. Al80s I used when I had to, but not my 1st or even 3rd choice. Steel cylinders made more sense in my area and with my students who were going to dive the Great Lakes, North Atlantic, and Florida caves.

 

[lowwall]

Looking to get into cave and wrecks. I likely won't travel with them so primarily, cold water, dry suit in upper midwest

If you are buying new, get HP100. They are close* to the same physical size and internal volume as the LP72 and LP85 mentioned above. Even if you can't get them filled to the full 3442psi, you can always get them filled to at least 3000psi which gives you 89 cubic feet of gas. They are also probably the easiest tank to resell.

But if you can get used LP tanks cheap, then it's time to explore what kind of fills you can get from your LDS and where you'll be diving. If they are sticklers about following the rules, you will be stuck with the nominal capacity. Also make sure the hydro stamp includes a plus or you might be stuck with 10% under the nominal rating. If they will overfill to 3000 psi, then the LP72 gives you around 86 cubic feet and the LP85 around 95. But you do have to weigh the risk that the shops will stop offering overfillsat some point.

* Tank - length x diameter (inches), weight (pounds) - all without valve
LP72 - 25x6.9, 26
HP100 24x7.25, 33
LP85 - 26x7, 31

 

[NothingClever]

…it's time to explore what kind of fills you can get from your LDS and where you'll be diving. If they are sticklers about following the rules, you will be stuck with the nominal capacity. Also make sure the hydro stamp includes a plus or you might be stuck with 10% under the nominal rating.

This.

While the LP85s have great buoyancy characteristics, I find the number of places in Florida I can get a cave fill is limited.

I just want to show up at a dive shop and get the volume I need without requiring any convincing, secret favors, insider relationship, etc.

Before buying LP tanks, you definitely want to call the dive shops within your tolerable driving range to confirm whether they’ll fill them past the stamped service pressure to what you’re expecting to get.

I’d go for the HP100s.

 

[OMyMyOHellYes]

steel will be faber and aluminum will be catalina.

Be safe

Unless the aluminum bottles be Luxfer. Or Metal Impact. Or Thunderbird.

 

[rjack321]

What SM BC are you using? How much gas do you need for the dives you're doing or aspire to be doing?

 

[The Chairman]

I'm not a SM guy but my buddies like LP85s for it.

They are sweet. I own LP120s and they are a bit heavy.

 

[halocline]

I would look around for a used pair of either HP100s or LP85s. For the HP100s, make sure they are the ‘special permit’ 3442 PSI version, not the 3AA 3150/3500 (+rated) tanks. Those are not very common, so you probably won’t encounter them, but they are quite negative.

Someone posted that you should consider what type of fills you can get, and that is excellent advice. Most dive shops outside of cave country in FL are not going to overfill tanks. In fact, for LP85s, the stamped pressure is 2400, and you might have trouble finding a shop that will fill them to 2640 (that’s the allowable 10% overfill if they have the plus rating) because many recreational shops simply don’t know anything about steel tanks, or they have restrictive fill policies that are dumbed down to the least knowledgeable employee. Then there’s the whole issue of getting the plus rating renewed at hydro time. I had nightmares trying to find a hydro shop in TX that would do it. It was very frustrating.

Those considerations point you to getting HP100s. The Faber FX100 is a really nice tank, but I’ve never used them for sidemount. They are slightly more negative than LP85s, and the thinner profile of LP85s is supposedly very nice for SM. (I use AL80s, so I don’t know how they sit) You just need to do some research to find a local shop that will fill them correctly.

You didn’t mention what your budget is. If you want cheap and plentiful, AL80s are ok, even in cold water, for SM. You’ll have to wear more weight and you have to re-clip them during the dive (every cave diver in Mexico does this on every dive, it’s no big deal) If you can find galvanized LP72s with 3/4” valves, they are really fun tanks to dive with, usually available for $50 or less, and they are my favorite tanks for shallow dives. You just don’t get much gas unless they can be overfilled, and most shops are not going to do that. They see ‘2250’ stamped on the side of a very old tank and get pretty squeamish, in my experience.