Ordering two BM O2ptima's with Nerd 2's need help with Options

[Zebra 1]

Thank you,
Just heard back from Dive Rite. They said the standard configuration is Petrel 2 as the controller and Nerd as a secondary monitor, so we're going that rout.
Dive Rite said the Nerd controllers are mainly sold with the CM unit, not sure why. Down the road we will convert to the CM when traveling overseas (Bonaire!).

 

[Zebra 1]

The O2ptima comes with AL20 2L bottles. We can also use 4L lp27's which together would add 5.2 lbs.
We are going to need extra bottles, what are the pro's and cons of between the two?

 

[tbone1004]

Thank you,
Just heard back from Dive Rite. They said the standard configuration is Petrel 2 as the controller and Nerd as a secondary monitor, so we're going that rout.
Dive Rite said the Nerd controllers are mainly sold with the CM unit, not sure why. Down the road we will convert to the CM when traveling overseas (Bonaire!).

Chest mount is sold with the NERD as a controller because it lets the unit be more standalone without something tied to your wrist. Many of those divers won't have a secondary monitor on there. Personally I think they should all have NERD controllers as standard and I frankly don't understand why that isn't the case. If you're doing things that are distracting, i.e. spearfishing, having everything in your face is a big advantage instead of just a blinky light.

The O2ptima comes with AL20 2L bottles. We can also use 4L lp27's which together would add 5.2 lbs.
We are going to need extra bottles, what are the pro's and cons of between the two?

You'll fill the bottles a lot less often and it knocks some ballast requirements off

 

[Zebra 1]

Yeah I want to skip the whole blinky light thing, does a controller give me any important information the monitor doesn't?

 

[tbone1004]

Yeah I want to skip the whole blinky light thing, does a controller give me any important information the monitor doesn't?

not in particular, but it does allow you to have "THE" device in your face and your aux device on your wrist. If you go the "normal" way, the primary device is on your wrist and the aux is in your face. Personal preference I guess, but I'd always rather have the primary device as the one that I'm looking at all the time.

 

[Zebra 1]

I'll keep it standard, should be some value in that.
What is the advantage of 4 O2 cells over 3 other than just another data point?

 

[Dusty123]

Keep your controller on your wrist. While you are learning your instructor will be alot happier if they can glance at that when you are learning all the skills. I learned to dive a rebreather in the ocean and just recently took it into a cave. I learned two different approaches with what to do with loop hoses when you bailout (if you skip the bov route), both cases the nerd is alot less useful than a wrist mounted controller if you needed it. Probably more of a thing on how my revo is setup with the nerd being a monitor. Nerds are definitely a great way to add redundancy for deco but have tradeoffs like anything. There are many schemes to mount them so they stay put and staying put in the right spot can be problematic vs blinky light which is tiny and unobtrusive. Just some thoughts.

 

[rjack321]

The O2ptima comes with AL20 2L bottles. We can also use 4L lp27's which together would add 5.2 lbs.
We are going to need extra bottles, what are the pro's and cons of between the two?

al19s are 3L bottles
lp27s are 4L - and huge and heavy

The 27s are way overkill. You are much better off having 2 or even 3 sets of 3Ls with potentially different dils (or all the same)
Depending on the (ocean) profile I can get 2x 200ft dives off a set of 3Ls, so 3 sets is a long weekend.
4Ls are 3 dives for me

 

[tbone1004]

Keep your controller on your wrist. While you are learning your instructor will be alot happier if they can glance at that when you are learning all the skills. I learned to dive a rebreather in the ocean and just recently took it into a cave. I learned two different approaches with what to do with loop hoses when you bailout (if you skip the bov route), both cases the nerd is alot less useful than a wrist mounted controller if you needed it. Probably more of a thing on how my revo is setup with the nerd being a monitor. Nerds are definitely a great way to add redundancy for deco but have tradeoffs like anything. There are many schemes to mount them so they stay put and staying put in the right spot can be problematic vs blinky light which is tiny and unobtrusive. Just some thoughts.

why is a wrist controller with NERD monitor better than a NERD controller with wrist monitor? You should be running the unit in manual mode for all of class anyway and not messing with the solenoid hardly at all.

 

[Dusty123]

Why are you pushing something unconventional to a new ccr diver? seriously for what purpose?