Help in determining proper tank

[BVickery]

I live in FL and dive the keys with my wife. I'm about 6'7 and about 375 (dropped 15lbs since I started taking scuba) she is 5'5 and the difference in air consumption is pretty disheartening since she can dive 1 tank to my 2.

I know I'll never be able to match up exactly with her as far as air consumption, but would really like to be able to spend more time with her on the bottom and since her air consumption would also improve I'd like some advice about tanks, since our LDS only rents AL80's.

Should I go with HP or LP? Steel or AL? What size?

Right now leaning towards a HP 130 or so.

Any help would be greatly appreciated.

 

[Hallmac]

What I would do first is figure your average sac rate. Then take the average dive you do together and figure out how much air you need to carry.

What you need in volume will help you answer many of the questions. The size you require may limit the brand, style, and composition available.

 

[BVickery]

how would I determine my SAC rate? I'm pretty new to diving and our instructor never covered how to figure it out.

 

[Hallmac]

Here is a good read, if you still have questions I would love to help.

http://www.scubaboard.com/forums/basic-scuba-discussions/240133-calculating-sac-rate-rmv.html

 

[elan]

I would recommend you to do more dives before you make your final decision. While a big tank is nice to have your SAC rate will mostly drop. I went through this recently and my SAC rate has improved 1.5 times after I sorted out some of my skills. Though women generally consume less air you might get to the point when you will both hit NDL faster then you run out of air. You can do a lot of things with AL80. They are cheap, available everywhere and hold pretty much air for most rec diving in my opinion (at least shallower than 80ft).

You can use this link for the calculations

http://www.spearfishing.org/bruces_tips/java/sac.html

 

[BVickery]

Here are my last 4 dives.

0.93 (3rd OW dive)
1.25 (4th OW dive with major buoyancy problems though weight used on dive 3 didn't change)
1.26 (first dive as a cert. diver)
1.10 (Spring dive)

Going down to the keys in a few weeks and Chris from Silent World generously offered to help me sort out some of my weighting issues to help improve my SAC.

 

[elan]

You definitely have space for improvement, do not rush with the decisions yet, just get some more dives and you will see it will get better.

 

[diver 85]

You're no little thing---I'd go with a HP 120 or 130(leanning to the 120) if you're trying to 'even things up'----can never have too much air down there.......

But, that's just me......

 

[Hallmac]

Going down to the keys in a few weeks and Chris from Silent World generously offered to help me sort out some of my weighting issues to help improve my SAC.

Based upon your posted dives, and this information I would suggest you hold off on your purchase for just a bit longer. Keep renting and just work on getting comfortable first. Keep logging the dives and working out the RMV and SAC. You are going to see some real improvement and your RMV will start showing a bit more consistency. As long as you are trying to stay within the same type of diving and equipment use.

Once you see what you believe is a somewhat consistent value, you can then make an informed decision.

welcome aboard.

 

[Graeme Tolton]

another suggestion would be to buy a couple of AL80's for now and get some practice in. This way, you won't be renting tanks and in the long run, if you decide to buy larger tanks for yourself, your wife will be able to use the al80's you already own.