A 7' hose question when diving doubles

[syntaxerrorsix]

I have a question: What single tanks are you currently using, and if they aren't HP130s or cave-filled LP121s or some other rather large tank, why go to doubles? That's a lot of complexity, change, and burden (on land or boat) for a few extra minutes of bottom time.

Redundancy.

Also, all but the extremely minute of doubles can get you into serious deco on just about any recreational dive. For a 100-foot wreck dive using 32% I am bored and cold before I hit my NDL, and using my AL80 doubles I have over half of my backgas left when it comes time to ascend.

More gas will not get you into deco. Poor situational awareness will.

Even if you are doing shallow reef dives (20-40 ft) an HP120 or 130 will give even the hungriest of divers plenty of time to enjoy things, without the learning curve of a set of doubles. And don't forget, unless you are finding on screaming deal on a set of dubs, buying two new single tanks will be much cheaper than than buying a new set of doubles.

Peace,
Greg

It's not hard to learn how to dive with doubles and there's a myriad of reasons why someone would want to.

 

[Cave Diver]

A long hose is not necessary with doubles. However, I believe it is a good idea and even use a 7' hose when Im diving a single tank. The advantage is that in the event of an other diver needing your gas they can breath from the more comfortable 7' hose. It is also about the configuration. With a 7' hose you donate the 2nd stage you breath from, this makes it faster to donate (as you dont have to fiddle around finding it). It also means that your alternative 2nd stage is right there so you dont have to fiddle around for that one.

Ditto that. Also, if you're using doubles to go deeper or stay longer as you say, please be sure you get the appropriate knowledge to do so. It's not simply a matter of strapping some extra gas on. There are other things to consider as well. You may wish to look into an advanced nitrox course if you haven't already done so.

 

[Superlyte27]

what syntax and cave diver said

 

[HowardE]

Is it really necessary to use a 7' foot hose when diving doubles? I am not a cave diver and I intend to use doubles only to stay more under or to go deeper. Thanks

You can use whatever size hose you like. There are no rules in Scuba when it comes to finding your personal preferences with comfort and fit, contrary to what some people may tell you.

I dive double 55's most of the time when I'm diving even in shallow water. Mostly, because I like the added weight they provide me, they trim out nicely for swimming, and they offer redundancy.

As for your desire to dive longer and/or deeper - I'd say this: What some people would refer to as common sense would dictate that you shouldn't exceed your training level when making deeper or longer dives. Don't exceed no decompression limits, or dive deeper than recreational limits without the proper training.

 

[tbone1004]

On top of redundancy, doubles are MUCH more stable IMHO. I dive SM, but if I have to backmount, I'll put doubles on anyday, just because they're a lot more stable in the water.
When I'm in OW, I don't put a long hose on. It's not necessary. Will it make deco more comfortable, sure, but 5' is plenty, and especially with a 90* adapter on the hose, it's plenty. I dive with short hoses in open water, and they force you to hold onto each other when you have to share air. If my buddy ran out of air, or something failed on his equipment, his heart rate is gonna be higher as are stress levels. I'd rather have contact with him to make sure he doesn't panic and bolt to the surface.

 

[Michael Kazma]

As others have said...About the diving doubles to stay down longer and deeper-There is much more to deeper and longer and diving doubles. If diving doubles, isolation drills should be second nature to you. Also, if you are diving doubles to stay down longer and deeper then you are almost definitely running into deco. When diving deep and doing deco then you SHOULD be decompressing on higher O2% than air. This means that you should be at least certified as an advanced nitrox diver.