Single Tank Sidemount

[MScorpa]

[FONT=Verdana, Arial, Tahoma, Calibri, Geneva, sans-serif]I am going to be doing some shallow open water dives with rental tanks and have been doing a bit of training using single tank sidemount. I was wondering what everyone's thoughts are about this configuration and how you like to setup your equipment? Any tips would be appreciated.[/FONT]

 

[DevonDiver]

I very rarely dive single-tank sidemount, but I have played around with it before. I don't find it offers significant benefit over two-cylinder sidemount and, obviously, doesn't offer the benefits.

I swap the long-hose across to the right and leave it fully stowed during the dive (breathing off the short hose). Air donation from the bungeed/stowed long hose.

 

[Glenn08]

I haven't tried sidemount, single tank or otherwise, but I have wondered about sidemount with a primary and a pony. Does anyone dive sidemount with different size tanks ?

 

[a878bob]

I love it for warm blue water and pretty fish. I clip my cylinder on the left. 6" hp hose and SPG routed down, 40" octo routed down and back up the cylinder under bands, power inflator hose routed down under bands ( never used it yet, probably could do without). 30" 2nd stage routed up and behind neck with right angle adapter. I clip in upper and lower and then bungie up when I get under. Reg faces out, bungie around valve handle. Easy!

---------- Post added September 4th, 2013 at 05:32 PM ----------

Oh Yeah, my own homemade stage rig to go on the rental cylinder. Nice handle and I use my scubapro quick release cam straps to secure. Easy on, easy off, fast!

 

[MScorpa]

Andy, reason for diving single tank sidemount is that I will be with other single tank divers at a shallow depth in open water (so no need for more air than that), it will be a rental tank so no left hand valve available, and bringing my sidemount harness is a lot more compact and lighter weight than a back mount bcd for travel.

For configuration I was thinking I would breathe the standard short hose on my necklace and stow a 40" hose for air donation on my tank. Do you think I should stick with the long hose? I thought it might be a bit overkill.

Glenn, The only way I've ever dove sidemount with different sized tanks is using twin primaries and a 40cf stage. I don't really know why you would want to dive with a pony? If its open water and shallow then a single is fine, otherwise I'd only dive matching primaries at a minimum.

Bob, sounds similar to how I was setting up my equipment (minus the stage rig and inflator hose routing).

 

[DevonDiver]

Andy, reason for diving single tank sidemount is that I will be with other single tank divers at a shallow depth in open water (so no need for more air than that),

I prefer diving two tanks, even for recreational. There's ample gas for two dives on those two tanks and you get the added benefit of the redundancy and 'carrying forward' your unused reserve from the first dive onto the second (you get an 'extra' 50bar on the second dive).

Diving one tank sidemount really isn't any more comfortable or convenient than diving one.

it will be a rental tank so no left hand valve available,

I dive rental tanks day in, day out with sidemount. Rarely do I have the 'luxury' of having left-handed valves. It makes no odds, if configured appropriately.

For configuration I was thinking I would breathe the standard short hose on my necklace and stow a 40" hose for air donation on my tank. Do you think I should stick with the long hose? I thought it might be a bit overkill.

I have a 40" short hose anyway LOL. 2m/7' hose is nice for air-sharing - it stows nicely under bungees on the tank (a 40" wouldn't). There's no real 'overkill' in respect of task loading or complexity. It's also there with you, should you decide to swap back to two-tank sidemount.

I'd use two tank, for sure, on any deep dives (18m+) or if penetrating anything.

I have wondered about sidemount with a primary and a pony. Does anyone dive sidemount with different size tanks ?

You *could*, but why would you? It's sidemount...

It's be like buying a Ferrari and filling it with diesel..

 

[tphelps]

I haven't tried sidemount, single tank or otherwise, but I have wondered about sidemount with a primary and a pony. Does anyone dive sidemount with different size tanks ?

@MScorpa: Pretty much what Andy said. The main value of sidemount is the redundancy. Take that away and it somewhat defeats the purpose of sidemount. I have done "monkey diving" before (aka single tank sidemount) but that is when I am doing a short, shallow, shore dive. The ideal thing to do would be reconfigure your long hose into the single tank so you still have an alternate air source for your buddy. Personally I find it awkard but dont let me tell you how to enjoy your diving! If you do get into single tank sidemount then I would look into some sidemount harnesses. I personally have a UTD but there are many manufacturers now. You will want some bungee cord to stow your excess long hose. The rest like D-rings and bolt snaps should come in your sidemount system. After that, its all practice practice practice to find where your tank bands should be and how much weight do you need to compensate.

@Glenn08: Like others have said on here, the main value of sidemount is the full redundancy. A primary and pony bottle (like a spare air) to me, is barely meeting the requirements of a "self reliant diver." It is possible to sidemount with different size tanks but then that just throws your trim off. I mean I like the idea of an AL80 and an AL40 more than an AL80 and a pony bottle. I dive sidemount with the same size cylinders.

 

[Quero]

I used my sidemount rig on my recent Florida trip. I was diving in a bunch of different environments, for most of which I carried two tanks. But I did do some diving at the Blue Heron Bridge, which is an exceedingly shallow dive (5-7 meters) for which all that redundant gas would have been overkill in the extreme. I chose do do my diving there with just one tank and with weight on the other side of my body for balance. It worked okay. I wouldn't want to do it routinely, and when I don't feel like I need two tanks I normally just use my single-tank back inflate, which isn't really any heavier to pack than my sidemount when I consider all the extra hardware I need for sidemount diving. But because of the other diving I was doing in sidemount, I really needed to travel with my sidemount rig. I definitely feel like it was a kind of a tradeoff to use just one tank with my sidemount rig--I would have preferred my backmount rig for the BHB diving.

 

[drbill]

Personally, as a videographer, I would think single sidemount would be pretty unbalanced, but I admit I've never tried it. However, when I mounted my pony on my main tank off to one side, I found I had to compensate with additional weight on the opposite side of my belt to prevent roll. Is this an issue for single tank sidemount?

 

[thez_yo]

It takes a couple dives to get used to single-tank sidemount, but soon enough you figure out how to compensate with one fin to get back to well trimmed out. I put the single on my left side, and then my left foot has to kick a little harder, but nothing exhausting by any means. Other people say it's about how you position your hips, but whatever works is the right way - it all depends on the shape of your body (like exactly where you need those last couple weights to trim out head-to-feet too). If you shift your weights to compensate for the full tank at the beginning of the dive, you might have to compensate for being heavier on the extra-weight-side by the end of the dive depending on the buoyancy characteristics of your tank.

That being said, double 40's is nice too if you don't need all the gas of double 80s and can find some.