New to diving in the uk

[Wibble]

Was diving in Scapa Flow in May one year, water temperature 9 degrees. We were diving 1h30 or thereabouts in our drysuits.

On the boat was a Scottish chap with a thick wetsuit and a shortie over that. His dives were 30 mins or less and immediately ran into the shower to warm up! Kudos to him for diving wet, but phew, much rather be warm(er) in a drysuit.

 

[Edward3c]

Another thing is cylinder size.
Does size really matter?
12 litre or 15 litre which is best?

This could start something.

You will get an extra 696Lt of gas, but the buoyancy change between a full and empty (to reserve) cylinder will by over 3kg. Whereas a 12 will be just over 2.5kg plus a 15Lt weights an extra 3kg. From my observations when students drop from a 15 to a 12 their dive gas consumption improves as they’re not having to more the extra mass. As a result their dive times are the same, but more often improved.

 

[Wibble]

Early days diving you're only going shallow and short dives, therefore a 12 is fine.

Doing real dives on a 12 is fine unless you're going much deeper, e.g. beyond 30m, where you need more reserves.

So a 12 is fine.

Also... you can get a 300 bar cylinder, rather than the standard 232 bar cylinder. In theory this gives you more gas. In reality it's hard to get a 300 bar fill; the cylinder's heavier than a 232 bar cylinder; the regs need to be 300 bar sized (which most DIN regs are).

In other words... don't bother! More hassle than it's worth. I did this when I started UK diving and quickly found it was pointless!

 

[BoltSnap]

I have 12, 15 and 18L 232bar tanks. The only time I use the 12l tanks is is in pool for when I am teaching or when my 15 and 18l haven't been filled and I need to go diving before filling them. My most used tanks are my 232bar 15L tanks. They are the best all around tanks for shore and boat diving. My 18L tanks are used infrequently when doing deep boat diving.​

​

In short, I recommend the 232bar 15L tanks.​