Aluminium 100's, Steels, and Breath Control...

[dbg40]

Don't go nuts, generally speaking a woman will, almost without fail, best you on sac.
Just the way it is, less mass to shove through the water, and less muscle to do so = better fuel mileage!

 

[starpilottom]

I own a pair of AL 100 tanks and I'm very happy with them. I purchased them for the same reasons you are considering buying yours. I do my best to max my air consumption but it really comes down to a matter of size. Being 6' 3" and 240 lbs I have more water to move out of the way and more O2 burning tissue than many divers. Good technique will help close the gap as I've surfaced with more air than some divers half my size when using the same tank. It comes down to a percentage thing with you and your lady 100's should help close the gap. Also some liveaboards allow you to request 100's. Nekton uses steel 96's as standard. I do get annoyed when I request 100CF tanks and I get the "I don't know anbody who uses them response or why would you want them response" I feel like telling them that divers come in all sizes not just midget and medium and your just too cheap or lazy to look at what bigger people are coming aboard with. The ones that don't have to fly that is.

 

[jonnythan]

Whoa, I just looked up the specs on those Al100s...

They weigh more than my PST E8-130 steel tanks!!

 

[Wayward Son]

I also dive some AL100's and like them.

Why? Bc I can afford them. I want steel 100's & agree that they are superior in many ways. But they can be handed down from God on high & it doesn't make a flip if you can't pay for them, which is where I'm at right now.

I've been fortunate to snag 3 of them used. One simply took a new AL80 traded even (cost me $135 for the 80, and I was about to buy the 80 any way). The last 2 cost me $80 each with a new hydro & VIP.

In comparison, E7-100's are running about $350 each, when you can find them. Do the math:

3 used 100 AL tanks for a total of $295.
3 new 100 E7 tanks are $1050.

I'm a rec diver who mostly spera fishes. I have no technical needs that justify the extra cost of steel tanks. I prefer their size, weight & bouyancy characteristics over AL, but I can deal with the AL just fine.

Since I don't have the cash for all those steel tanks, it's a moot point. I can have & use the AL now, or I can have nothing until I can buy the steel tanks in what looks like 2 to 3 years from now. Put in perspective, those big AL tanks make me pretty happy.

 

[dbg40]

Steels are a tough nut to crack ($$$$!!!!) and can kill an entire dive budgett in one shot. (possibly even two budgetts) I was very fortunate to have a good relationship with my lds owner, who called me with two HP 100's he took in trade. $400.00 out the door with fresh hydros. If not for that, I would have had a tough time getting into any more new steels! I have logged a many a dive on AL tanks, and could go back to them without issue, if needed. Its not what you dive, its how you dive them ;-) Personally, I think that aluminum tanks get this sport way closer to the budget of real world divers. Wayward son is right,, you can dive AL now, or have nothing. And the diference between the two is a new Halcyon, or a sweet Apeks rig!

 

[Jim Lapenta]

Have two pst 80's and they are fantastic. I'm a little shorter (5'7") and the fact that they are not much taller than a 50 are perfect for me when going backwards off of boats or when doing a seated entry. Their buoyancy characteristics are what really justified the extra cost. in my 3/2 shorty an al80 requires about 8 lbs for me. the pst's let me cut that in half. It also helps in the drysuit by reducing the weight requirement from 28lbs to about 24. I also have 3 steel 72's that while not as fun to dive as the 80's still let me dive with less weight. Total outlay for them was 50 bucks each with new hydro's and vis. Our lds is replacing their steel 72's with the pst'80's,we still have al80's but I don't dive em. Plus the pst's are rated at 3442 so I'm normally getting good fills of about 3600-3800 once the tank warms up in our lake where the water is right now 91 at surface and 88 at 92ft. Some others have suggested working on your trim and technique which is cool. My air consumption has been dramatically reduced with proper buoyancy and breath control. last outing first dive was multi level altitude to 92 ft(116 alt adjustment) for 8mins then up to 50 for 10 mins then to 35 for 14 mins add 4 min safety stop with 2min ascent along bottom from stop to surface. Total bottom time of 34 mins. beginning pressure 2700 in steel 72 ended dive with 1700. Compare with first dive to 92 ft in aow course 63 dives ago which lasted 22 minutes including safety stop and used 1800 psi. Now when I switch to nitrox which is what I keep in my 80's I can get around 2 1/2 hours out of a tank if most of the diving is in the 35 ft avg depth range when assisting with students. Would I like to have some 100's or even 95's yeah but for now I don't need em. The time is coming though, probably within the next year and a half, when I'll be putting together a set of doubles and am leaning towards using two more of the steel 80's. That should give me enough air to do anything I need to.