15L vs 12L for beginner

[Patoux01]

Any weight I save on my tank has to be added to my BP or my belt.

Sure, but that weight placed on your belt, bp or harness has a smaller influence on your position in the water, as it won't create a high torque (due to its distance to your body).
Which is exactly why I would not use a (very) negative tank if I could avoid it. The same goes with a very positive tank, though carbondives can easily have some weight added to them (sort of defeats their purpose of being light-weight, but they'd still be lighter than a 12l tank, and contain more gas).


This is because I'm the kind of guy that will spend half a dive on his side because he can. If you spend your whole dive horizontal (or vertical), it doesn't matter too much...


I've probably just been traumatized by my 15l tank turtling me the whole time during my OW course...

 

[Storker]

I've probably just been traumatized by my 15l tank turtling me the whole time during my OW course...

That's plausible

As long as I avoid the monster 15x300, IMO it really doesn't matter much WRT balance underwater whether I use a 200, 232 or 300 bar tank. In fact, a 10x300 is a lot slimmer than a 15, so it'll put my COG closer to my back, and IMO it's slightly more comfortable to dive than my chubby 15x200. But this is of course a question of personal preferences and those small differences in gear setup.

 

[babycover]

so in conclusion, a twin set is better then a single tank but if you go single tank a 15 would be good and recommended 232 bar. is that correct?
im not sure Ocean diver shop fill the 15 to 300 but they do fill the 12 to 300. just leave it with them over night.

at this point i would go with the 15 232bar

thank for your advices

 

[Storker]

so in conclusion, a twin set is better then a single tank

No, but a small twinset is better than a whopping big single with similar capacity. OTOH, If you don't need to carry more gas than a normal single can take, one or two moderately-sized singles may be better. That's my preferred solution. Because the smaller the total tank volume, the less your rig incl. belt will weigh.

I prefer swapping tanks between dives rather than lugging the gas for both of the day's dives on dive #1 of the day. Others may prefer a twinset, e.g. for having their COG closer to their back. A twinset with enough gas for two good dives would be like a D12x232, and that's something few rec divers are motivated to lug around.

 

[Patoux01]

so in conclusion, a twin set is better then a single tank but if you go single tank a 15 would be good and recommended 232 bar. is that correct?

Does that actually hold enough gas for your 2 dives? I'd do the calculations quickly, my typical 2 dives used about 3300l of gas, which is pretty much the full content of a 15*232...

 

[Storker]

If a 15x232 holds enough gas for two dives, either those dives are very short and shallow, or the diver has about the same gas consumption as a mouse. When I had my 15x300, it was good for either one dive beyond NDLs, or two rather short-ish dives.