Charred
Contributor
There are some great older threads in the BCD forums about wing size by Tobin formally of DSS.
Surface issues aside, the wing is there to compensate for things that change in buoyancy (I hope you see what I did there...) during a dive. Thus your wing has to deal with wetsuit compression and the change in tank buoyancy. You ultimately need very little when wearing 3mm suits and AL80 tanks will go positive as they empty. Hence many people use 17-18 lbs wings. I think these threads make great reading (and some are very entertaining...).
If you ever dive with no wetsuit the above becomes crystal clear because you will need a small puff of air at the beginning of the dive to compensate for the 6 lbs of air in the tank.
I personally dive an 18 on a steel backplate with AL80s and a 3 mm (which half the time I don't wear). My wife has a 23 since she is often in a 5 mm.
Surface issues aside, the wing is there to compensate for things that change in buoyancy (I hope you see what I did there...) during a dive. Thus your wing has to deal with wetsuit compression and the change in tank buoyancy. You ultimately need very little when wearing 3mm suits and AL80 tanks will go positive as they empty. Hence many people use 17-18 lbs wings. I think these threads make great reading (and some are very entertaining...).
If you ever dive with no wetsuit the above becomes crystal clear because you will need a small puff of air at the beginning of the dive to compensate for the 6 lbs of air in the tank.
I personally dive an 18 on a steel backplate with AL80s and a 3 mm (which half the time I don't wear). My wife has a 23 since she is often in a 5 mm.