What's the most popular tank size?

[Loneranger]

Fun question, before the dive computer it was rare to see anything but AL 80's being used for tropical diving. The computer enabled the bottom times to be stretched so the AL 100's started making an appearance. With the introduction of Nitrox it is rare to see AL 80's being used anymore. I got off a boat 2 days ago and commented that there were no AL tanks on board, just oversized steels.

 

[divinginn]

the hp 100 is several inchs shorter than a al 80 and shorter than my steel 72s by a inch or so,the last few times diving im comming up with 1200-1500 lbs when my dive buddies are at 500 on al 80s,i see no problems having extra air,alot more options if mr murphy decides to visit. cant wait to buy another hp 100.

 

[Mossman]

With the introduction of Nitrox it is rare to see AL 80's being used anymore. I got off a boat 2 days ago and commented that there were no AL tanks on board, just oversized steels.

I wish.

While it's certainly nice in places like Florida where you can rent bigger tanks if you don't live there, and I have my bigger tanks for diving the frigid waters of SoCal, the AL80 is alive and well in all the tropical locations I've visited. Cozumel has a few shops offering bigger tanks, and I've rented AL100s in Grand Cayman, but the only liveaboards where I've found bigger tanks were on the Nekton Pilot and the Truk Odyssey. Everywhere else, the only option besides the AL80 is something smaller.

 

[somewhereinla]

So if I went with an HP Steel tank, would I need to change my reg. from yoke to Din to handle the extra pressure?

 

[spectrum]

So if I went with an HP Steel tank, would I need to change my reg. from yoke to Din to handle the extra pressure?

Nearly any modern regulator will be OK from a pressure standpoint. Your manual or dealer can confirm this.

If by HP you mean the pseudo HP cylinders rated at 3442 PSI you can probably use your yoke if you want to, again check the specs. I prefer not to, I have friends that do however. If you end up with an HP cylinder rated at 3500 PSI it will require a DIN connection, generally you would only find this as a used cylinder these days.

For cold water diving a 3442 PSI series cylinder is a beautiful thing.

Pete

 

[speleodiver6]

I dove 65 cf HP steels in Hawai'i for my shore dives, typically 60 minutes at avg depth of 45-50.
I reserved my 80 cf HP steels for deeper dives (70-100 ft)
Currently my favorites (necessity actually) are double E8-130's steels for cave diving.

Dive safe,

Celia

 

[ron63]

Maybe this question doesn't make sense, but someone mentioned having to switch to DIN if using HP steel tanks. Why would you have to switch to a DIN valve when AL80 tanks are HP?

 

[cummings66]

AL80's are not HP tanks.

When you look at 3500 PSI vs 3000 PSI you should see a difference and that's why one is an HP tank and the other isn't.

As to an HP 80 standing a 6' diver on their head, I'd say it depends. I'm 6' 180 lbs and can dive anything from an HP 80 to an HP120 without standing on my head. To be honest the HP80 was very very nice and resulted in very good trim for me, the HP 100's are next and I'm a bit tail heavy with the HP 120. Nothing seriously out of whack and easily compensated for.

So, go by the you're this tall so you need at least this size tank with little more than a grain of salt. Dive the tank size you're interested in and see how it affects you. In diving many common bits of wisdom apply to some but not all divers, like drysuit divers needing ankle weights or gaiters. Not true just as certain size tanks needed for big guys vs small guys. I've dove with large divers who sip air and skinny divers who suck it down.

Try it if you can before you buy it in other words, you may be the exception.

 

[somewhereinla]

Thank you all for your advices and wisdom... I think I am starting to get a very good sense of what I need and what to look for.

 

[Stu S.]

Hey, divers. Many HP cylinders come with the DIN/yoke combination valve. Some of us use a yoke regulator on these with no problems. DIN appears better, but the yoke has worked for me.