Another reg

[rjack321]

You don't really need two regulators even if the manifold has two regulator fittings. If you are only using one regulator, you MUST rinse out and blow out the unused fitting after each dive.

In the old days, most double manifolds had only one regulator fitting anyway.

The important thing is to not dive beyond your training, experience and comfort level.

The boat's the OP wants to use require redundancy. 1 reg on doubles wouldn't satisfy them (for good reason). Nowadays you should probably put a DIN plug in the unused side to prevent catastrophic gas loss if the knob got turned by accident.

 

[WD8CDH]

Yes, it is up to the OP, even if he is wrong. I have seen an OP that thinks an octo on a single is a redundant air supply but an octo on doubles wasn't.

 

[Colliam7]

I am going to switch to doubles and was wondering if I need 2 regulators, one for each tank.

Do you have to have two regs to use manifolded doubles? No. Should you have two regs? Yes, you should. As ivobj and NorthWoodsDiver have outlined, you will want two first stages, and two second stages. (I personally prefer they be identical, but I not infrequently mix my regs on my doubles, as the need arises.) Having an octo on a single first stage would not qualify as a 'redundant air system'.

I am starting diving off NJ and most boats require a redundent air system.

I will echo the sentiments of several posters. It might be easiest (and least expensive) to start with a (larger) single tank, and a pony bottle as the redundant air source.

The simplest system that would comply with the boat's requirements and not be a longterm waste would be a 30 or 40cft aluminum cylinder slung like a stage. Whether that is optimum for you right now depends on alot of other factors, both gear, training, and future aspirations.

You can 'work your way 'up' to doubles if you wish. I started with a wetsuit and AL80. Went to a HP120, for more air on deeper dives. Added a AL40 (slung like a stage) as a redundant air supply for deeper coastal dives, anticipating that I might also want to use it as a deco bottle if I pursued decompression diving. Added a drysuit. Moved to a BP. Moved to double 120s. Added some double 80s (which are a great saltwater wetsuit rig, but leave something to be dersired, as rjack321 indicates, for saltwater drysuit diving). Yes, the expense keeps mounting, the gear inventory keeps growing. But, the evolution was financially manageable, and I was able to pursue the appropriate training along the way. Having said that, however, I started using a pony bottle without formal 'training', I did my first few drysuit dives without 'training', I changed to a backplate without any 'training', and my first 10 doubles dives, including several 120 ft ocean dives, were done before any formal training. All along the way, I sought out, and received, a lot of advice from my LDS, though. My point is certainly not that training is unecessary. Rather, you often learn the most by thoughtful / controlled experimentation, combined with training.

 

[LouieLouie]

The main reason to use doubles is that you have two complete and redundant sets of valves and first and second stages. The only other reason I can think of is that doubles often feel more balanced underwater than singles carrying a similar amount of gas.

"I need more gas" is not an argument for using doubles if you're a recreational diver diving within the non-decompression limits.

 

[WD8CDH]

Yes, it is up to the OP, even if he is wrong. I have seen an OP that thinks an octo on a single is a redundant air supply but an octo on doubles wasn't.

By the way, I didn't mean that the OP was wrong about needing or requiring redundant air. (I am a firm believer in redundant air) I meant that it's his rules and even if he is wrong, either follow his rules or go even better (with his permission of course).