What are the true advantages of steel tanks?

[Scubaguy62]

For some time I've been considering switching out of my AL80s and purchasing HP100's for me and HP80's for my wife (the scbababe is no giant )

I like the idea of the tanks' negative buoyancy when empty and the idea of about 4 lbs less lead. I also like the idea of the tanks being a bit smaller, which makes them easier to carry on your back and stow in your car and at home. However, the other day I was at a local LDS (of the many in the Fort Lauderdale area), and while chatting with the instructor, a flip side to the steel tanks was pointed out, so I seeking some advise from my SB buddies.

This instructor pointed out that other than the size of the tank, there is not much advantage for a rec diver to dive steel. He mentioned that the idea of shedding weight is a myth because the weight is not being shed, it's being shifted (you're now carrying it on your back as opposed to your waist and steel tanks are heavier); steel corrodes quicker than aluminum; HP tanks require Din regs, which he views as an unnecessary expense if you're going to remain within rec limits; the price of steel tanks is also something that he considers unnecessary.

I don't have a problem diving with AL80's, as I just add 2 - 4 lbs to compensate for their positive buoyancy when empty, and their size does not bother me. Now, short of size being an obvious advantage, especially for my better half, what are other advantages of steel over aluminum that I may be overlooking?

Thanks

Rick

 

[Gary D.]

I've got both and have used both the entire time I've been diving. When it boils down to which one, I don't care.

Gary D.

 

[simbrooks]

I was in the market for tanks, i have been using AL80 rentals so far. I have also been getting my nitrox cert together, so once i have the dives for that done all will be fine. Due to using nitrox, i thought, well why not get a larger tank to make use of that extra bottom time, to get a larger tank in AL, like the 100 or larger, you have to get a fairly big tank. There are LP steels and HP steels, what i have ended up settling on was some "MP" steels, the PST E Series, they arent quite rated as HP, but are close. I was looking at the E7-100 for my GF and E7-120 for myself. Looking at the stats on dive-rite express and other sites showed me that for a tank with a similar dry weight to an AL80, i can get the E7-100, 20 extra cubic foot and no need to overfill them beyond rated pressure. IF you so desire you can get them still with yoke or the 232bar/K (DIN/yoke) valves that allow a yoke reg to be used with them, i got 300bar DIN regs with using steel tanks in the future in mind.

Now from what i see, you can get the same amount of air in a smaller/lighter steel tank compared to aluminium or a larger amount of air in the same size/weight tank. Also you get the #'s shed off your weight belt/pockets. When i was shopping around i looked at size, weight (dry), buoyancy and capacity of the various major steel tanks out there and the typical luxfer AL tanks, the PST ones jumped out of the page as having a good range of stats. They might not be for everyone. Somewhere i read that you can get 30years out of a well cared for steel tank compared to only 15 or so for an AL due to the strength. To do this you have to keep the outside clean, take the boot off etc. The price is all that much worse, i am getting the tanks for 260 and 300 a piece (100 and 120) nitrox stickered and ready to go. I could get AL's for about 150, no great problem there in my mind, i am paying for a product i hope will last longer and give me more bottom time (when available) in what i consider to be a better package. When we get the tanks in (still on order), in fresh water my GF and i are only going to wear minimal weight, if any, and in salt still not that much - given this is FL you dont need much, but i required about 10/16# in a jacket BC and AL tank before, so all that weight has gone somewhere! I will get some AL80's one day, as stage bottles, but that is way in the future, i want to get the advantage of these tanks now.

Ultimately, it is your choice, you weigh up the pro's and con's about it all, is it worth the extra money for what you get?? I thought so, others too, some have found it isnt worth it.

BTW, call me a psychic, but i have the feeling this thread will soon move to the tanks/valves forum.

 

[netmage]

I like the idea of the tanks' negative buoyancy when empty and the idea of about 4 lbs less lead. I also like the idea of the tanks being a bit smaller, which makes them easier to carry on your back and stow in your car and at home. However, the other day I was at a local LDS (of the many in the Fort Lauderdale area), and while chatting with the instructor, a flip side to the steel tanks was pointed out, so I seeking some advise from my SB buddies.

Rick

I have two HP100's and two E8-119's. I love em. More air, less lead. Tanks are a bit heavier, but I get to pull 10lbs of lead off my weight belt vs the AL80. But I also get to do a 60 minute dive at the quarry going down to 70 ft for about 10 minutes. I dive fresh water, so I don't have the saltwater corrosion problem.

I'm a big guy, so w/ my 7mm and an AL I'd be looking at 35lbs of lead. Once I get down to the point where I'd be looking around 16-18, with my steel tank and 8lbs of lead I'll be dancing in the streets.

 

[simbrooks]

Although i considered the E8's, as the cavers and those who mostly shore dive use, i didnt think they were that great for use on commercial dive boats. The little racks they have mostly only accomodate the 7.25" tanks, at least around here.

 

[BIGSAGE136]

You get more air...better trim..wear less weight..& they make better chimes!

 

[simbrooks]

Oh i think also the nay saying of this local instructor might have been to get you to buy AL tanks as they usually have more of those in stock than the steel tanks.

 

[billseamon]

Discount Divers (SCUBA.COM) has the following interesting details on their WEB site on the tanks:

Hieght

 

[billseamon]

Discount Divers (SCUBA.COM) has the following interesting details on their WEB site on the tanks:

Hieght Weight Empty Buoyancy Full Buoyancy Empty Tank
20.0" 30.9 lbs -10.9 lbs -4 lbs HP 80
24" 39 lbs -14 lbs -7 lbs HP 100
26" 31.7 lbs -1.9 lbs +4 lbs AL 80

From these numbers, you save almost a pound from the tank weight and 8 pounds from the buoyancy, plus get a 6 inch shorter tank, all for about three times the cost.

I have 2 AL 80's that I don't use since I got a HP 100. I purchased the HP 100 when Leisure Pro had them for $218.00 and Discount Diver's met the price. Now their price for the HP 100 is $374.95. Not sure if that is worth the price.

 

[simbrooks]

These are prices and specs for Faber/OMS tanks, which are heavier and more expensive than the PST's

For the same kind of tanks with PST look at:
Height Weight Buoyancy Tank MSRP
____________Full Empty
20 28 -8.5 -2.5 E7-80 272 (although you can get them from 200)
24 33 -8.5 -1.0 E7-100 304 (although you can get them from 260)
26 32 -1.9 +4 AL80 130-140 i think

Which i find a bit nicer than the OMS ones, but to each his own.