80cf. to 120 ct. btm tm increase??

[scubafrog5]

Hey all, I am in the market for a bigger tank (looks like a x-7 120 steel tank) what I'm looking for is to increase my bottom time so I won't cut more experianced divers dives short when I'm on a club dive, also i'll be dedicating this tank to nitrox, so I guess my question is, is this a good way to go and if so should it increas my bottom time the way I hope?? Thanx

 

[NorthWoodsDiver]

Well lets look at a standard 80, say for ease of math that your surfacing with 20 cubic feet remaining in the tank. If thats the case then you could increase your bottom time by 2/3's (40 cubic feet) and still surface with 20 cubic feet remaining.

If your using nitrox it wont be as much of an issue but usually increasing one's bottom time significantly will push them into decompression which is a whole other thread...

there are other ways to decrease air consumption and increase bottom times besides increasing the size of the tank like streamlining your equipment, maintaining a good horizontal posture in the water, integrating cardio into your lifestyle, etc. Just saying a $400 tank might not be the best option, it takes time and experience to improve air consumption.

 

[lowviz]

Hey all, I am in the market for a bigger tank (looks like a x-7 120 steel tank) what I'm looking for is to increase my bottom time so I won't cut more experianced divers dives short when I'm on a club dive, also i'll be dedicating this tank to nitrox, so I guess my question is, is this a good way to go and if so should it increas my bottom time the way I hope?? Thanx

Diving the rule of thirds, a 120 is an 80 you can suck dry. It will also take some weight off your belt. Yes, there are better ways to improve your bottom time but a 120 will even things up a bit. It will also increase your sense of awe when you dive with a truly efficient diver who outlasts you on a 72. -don't ask...

 

[rjack321]

a hp120 is kinda a beast of a tank. its really tall and skinny.
a lp120 is stupid huge and only really exist in catalogs

you might want to consider a hp119 or hp130 instead
both are more popular, work on more divers bodies, and have way higher resalability

you are still going to use alot of gas and be turning dives comparatively early, just a little less early.

 

[dumpsterDiver]

I use/own lp 125's, 108's, 98's, 117 and also a 149 steel tank (about 3450 psi). They are great tanks!

I hardly ever use an aluminum 80 tank. If you are strong enough to use a big steel tank, go for it! My big single steel tank holds nearly what double 80's do and it is much lighter and easier to handle (plus I can often get more than one dive from it). The larger tank allows you to enjoy your recreational dive without worrying about trying to save or conserve air.

I hate it when these tanks rust, but the extra cost and weight is worth it for me.

 

[PvtStash]

LP 121 ... yeah its a monster, but I'm 6' 3" , 248 lbs. so not So big a deal...

like the way I use less wt. in the pockets now, and Really like being able to get 2 dives (approx. 40min) outta 1 tank... economical...(especially when I get a 2700-2800psi fill).

I may eventually put an H-valve on it as an in-between step before goin' Pony... (unless a good deal on a pony comes up)

 

[scubafrog5]

thanks all, you have all been helpful, this is what I joined the board for!