zimm, good question!

with only a shallow knowledge that i have, please allow me to answer. later sifus can correct me as i am also learning.

200 or 232 max bar or whatever is only the tank pressure and the limit of the tank can take. Normally what we use are all aluminum tanks. Obviously the lower the pressure indicates lesser air.

The size of the tank 11l or 8l indicate how much air it can take before reaching 200 bar. So, the bigger the size (or even you can use twin tanks) more air you have -->longer you can stay.

In summary, aluminum tanks has many capacities (in liters) and but they can hold max amount of pressure (in bar or psi). We let sifus explain more on steel tanks.

my two cents.

my dear demon......i always hv that question in my mind as when i go diving, i would rather use a smaller tank as its lighter la for me....and since snafu is here....(after cutting his hair)......i did ask him that same quesiton.....
he refuse to answer instead asking me to post the question in here so tat other ppl can answer or at least to learn somethin new.......so go ahead la......give me the answer........

Hahha..thank god he has cut his hair...Snafuette's been away too long in the Big Apple, our friend's hair all gone white because all the white tanni gone to his head.

We'll let the other instructors answer la...I'm just a novice.

I'll let the others answer

As for your "50bar left in both tanks" question...

unne rende rende rende une une rende rende.... time to ascend and do your saftey stop.



my two (non-instructor) cents.
 

Hahaha...good advice!

Ok Zimm .... you have the answer already.

I guess you be going back to a bigger cylinder after this.

 ;D

say i would like to go down 25m for 50mins......what would a 8L & 11L tank can effact a dive.
and my nxt question, wat if both tanks left wit 50 bar at depth

Hmm...this question has not been answered directly. It really depends on one's surface air consumption rate. For this purpose, let's use the constant of 15 liters/minute SAC rate. Why 15 liters? Just a number I'm throwing in.

With everything else remaining constant, at 25 meters, your air in a 11 liter tank will last you only about 41 minutes. You will hit 50BAR after 31 minutes into the dive. For you to do a 50-minute dive on this tank capacity, you will have to execute your dive at 19 meters maximum.  However, if you ascend to 5m to do your safety stop when your tank reaches 50 BAR, you will have an extra 24 minutes at that depth. So for all intent and purposes, you can actually do a 55-minute dive providing you also dive 24 minutes at 5m.

For a 8 liter tank, it would be a lot lesser bottom time. At 25m, everything else remaining equal, your maximum bottom time is about 30 minutes. You will hit 50 BAR 23 minutes into the dive. However, if you ascend to 5m to do your safety stop, it'll give you another 17 minutes at 50 BAR. So you can, in actual fact, have a 47-minute dive with an 8 liter tank,providing you love to see Lizardfish, Christmas tree worms and damsels only. ;D ;D ;D ;D ;D

Quote

tks guys.....but i still wish somewhere out there, there's a lighter tank yet carries the same pressure+volume of air so tat small ppl like us can carry la......sakit pinggang ooi (back pain ooi) :-?

Rebreathers sound like the perfect solution for you, Zimm  

Twin tank set-up at Panuba would also be out of the question as you have to walk all the way to the boat with it  ;D ;D ;D

Oi...I woke up early to give you one long answer and you never even bother to read  > ;D ;D

Quote

Oi...I woke up early to give you one long answer and you never even bother to read  > ;D ;D

;D ;D ;D ;D & i woke up early to read ur answer.......without my breakfast somemore.......hungry ni......
btw....appreciate ur time & answer
so in the future.....i'll try to skip the small tank la......& make sure other ppl will carry my tank to the boat  

Sure...sure...I won't join you on your trips then  

Quote

say i would like to go down 25m for 50mins......what would a 8L & 11L tank can effact a dive.
and my nxt question, wat if both tanks left wit 50 bar at depth

Hmm...this question has not been answered directly. It really depends on one's surface air consumption rate. For this purpose, let's use the constant of 15 liters/minute SAC rate. Why 15 liters? Just a number I'm throwing in.

With everything else remaining constant, at 25 meters, your air in a 11 liter tank will last you only about 41 minutes. You will hit 50BAR after 31 minutes into the dive. For you to do a 50-minute dive on this tank capacity, you will have to execute your dive at 19 meters maximum.  However, if you ascend to 5m to do your safety stop when your tank reaches 50 BAR, you will have an extra 24 minutes at that depth. So for all intent and purposes, you can actually do a 55-minute dive providing you also dive 24 minutes at 5m.

For a 8 liter tank, it would be a lot lesser bottom time. At 25m, everything else remaining equal, your maximum bottom time is about 30 minutes. You will hit 50 BAR 23 minutes into the dive. However, if you ascend to 5m to do your safety stop, it'll give you another 17 minutes at 50 BAR. So you can, in actual fact, have a 47-minute dive with an 8 liter tank,providing you love to see Lizardfish, Christmas tree worms and damsels only. ;D ;D ;D ;D ;D

Instructors and DMs out there, any other figure or inputs you guys want to add to this? Or dispute my calculation? Come, let's share our knowledge for the benefit of the community. 8-)

Quote

Quote

say i would like to go down 25m for 50mins......what would a 8L & 11L tank can effact a dive.
and my nxt question, wat if both tanks left wit 50 bar at depth

Hmm...this question has not been answered directly. It really depends on one's surface air consumption rate. For this purpose, let's use the constant of 15 liters/minute SAC rate. Why 15 liters? Just a number I'm throwing in.

With everything else remaining constant, at 25 meters, your air in a 11 liter tank will last you only about 41 minutes. You will hit 50BAR after 31 minutes into the dive. For you to do a 50-minute dive on this tank capacity, you will have to execute your dive at 19 meters maximum.  However, if you ascend to 5m to do your safety stop when your tank reaches 50 BAR, you will have an extra 24 minutes at that depth. So for all intent and purposes, you can actually do a 55-minute dive providing you also dive 24 minutes at 5m.

For a 8 liter tank, it would be a lot lesser bottom time. At 25m, everything else remaining equal, your maximum bottom time is about 30 minutes. You will hit 50 BAR 23 minutes into the dive. However, if you ascend to 5m to do your safety stop, it'll give you another 17 minutes at 50 BAR. So you can, in actual fact, have a 47-minute dive with an 8 liter tank,providing you love to see Lizardfish, Christmas tree worms and damsels only. ;D ;D ;D ;D ;D

Instructors and DMs out there, any other figure or inputs you guys want to add to this? Or dispute my calculation? Come, let's share our knowledge for the benefit of the community. 8-)

I'm no DM nor Instructor but my good friend can help me answer this question.
http://en.wikipedia.org/wiki/Diving_cylinder#Breathing_capacity

I'm no DM nor Instructor but my good friend can help me answer this question.
http://en.wikipedia.org/wiki/Diving_cylinder#Breathing_capacity

That's a good link. Thanks.