Gases for 50M dive

[JohnnyC]

21/35 + 50% + O2 for dives more than 30 minutes.

This.

 

[Nuribromanski]

air+36%+100%, 60/85 GF

 

[bakodiver391]

I do a LOT of sub 50M diving in tropical waters. Air plus 90% are my usual gasses. Some of the GFs posted look too aggressive to me. Maybe OK for a single isolated dive, but for repetative, multi-day diving I use 30/75. This has years of successful use by me and my buddies. I only post this because new tech divers may take these aggressive GFs posted by others as the norm.

 

[Peter69_56]

Air and 50 Nx, 80 Nx

+2 or +3

 

[Peter69_56]

I use 80 Nx for final deco over 100 Nx as it gives virtually the same result for less cost as well as having a little more margin for error given 100% is 0-6m where 80 Nx is 0-10m

Most here in Melbourne use air to 55m mostly due to cost of the helium. Although in saying that more people are on breathers now so they may tend to use trimix.

For me on OC I could not afford the cost of doing lots of dives on Trimix. The dive would have to justify the cost.

 

[JMBL]

Deeping on where I dive, but it could be :

- Air, GF 20/85, deco on air (there are indeed hundreds of place where air is the only gas available)
- Air, GF20/85 or VPM +2, Nx 50 for deco

When cold and dark :
- 20/30 + Nx 50, GF 30/70 or VPM +3