Is Sidemount an effective way to 2-tank dive Bonaire?

Hi:

Basically, I want to know if taking a sidemount course & buying whatever BCD-type, an extra reg. & whatever other 'parts' I'd need would serve what I want to do.

Me: Age 43, 6'1", ~275", chunky, non-smoker, not athletic & not likely to be, SAC rates from actual dives tend to run > .6 to > .8, averaging roughly around .7 or slightly over. Rec diver with no plans for Tec. Typical tropical Caribbean reef dive, I get around 45 minutes on an 80 cf tank; I can 'cheat' messing around in the shallows & get close to an hour, but that's bordering on snorkeling. I've got around 110 dives, cert.s (all PADI) are OW, AOW, Rescue, Deep & Nitrox, and I'm sort of an avid vacation diver (Caribbean warm water coral reef diver) who also dives a quarry in southwestern KY (Pennyroyal Blue Spring) periodically. I don't wear wet suits in water 75 degrees & up; I've got a 5 mm but prefer to avoid cold water.

I hope to get SDI Solo-certified this summer before a Bonaire trip.

My Gear: 2x Sherwood Avid BCD (jacket style), Atomic B2 reg., Air2, Cobalt dive computer, SeaSoft Sunray boots, TUSA split fins, Atomic sub-frame mask. At home, I use a 130 cf HP steel tank.

What I want Sidemount to do: I envy the 1 1/4 - 1 1/2 hour dive times some people get doing dives like mine. I've been to Bonaire 5x's, 6'th trip already planned, hope to return many times. For shore diving in Bonaire, I want to take 2 of the usual 80 cf EAN 32 tanks per dive, so I can get long dive times. Ideally, each tank would have its own regulator & SPG (Cobalt on one).

It's my understanding that diving doubles usually entails 2 dedicated tanks banded together with a manifold. I'm hoping sidemount will let me bypass those hurdles. I've never 'slung' a tank and don't know what all it entails, but I'm thinking for 15 or 20 dives in a week, even weight distribution & stream-lining would make sidemount make sense. I haven't boat dove in Bonaire yet & have no immediate plans to.

I've done some reading on the forum & elsewhere. I'm lousy at visualizing from verbal descriptions (you can't give me verbal directions to drive anywhere; I can't grasp it), and discussions tend to revolve around gear or brands I'm unfamiliar with (e.g.: Hollis, Dive Rite), applications I don't intend to use it on (e.g.: cave, boat diving), etc...

Sooooooooo, if I signed up for a PADI rec. sidemount course, grabbed an appropriate BCD & kit, could I run off to Bonaire for the typical 7 day unlimited shore diving package & dive 1 1/2 hours/ dive using 'off the rack' 80 cf aluminum tanks they provide, or is there more that I'm missing? Is swapping out tanks a big hassle? Do sidemount divers often use manifolds to connect 2 tanks to make one functional unit, and does that complicate matters for what I want to do?

Thanks in advance!!!

Richard.

I see no reason why you could not do that in fact you can make it even easier...

Just make a stage set-up and clip an AL80 off as a jumbo pony. Your Avid will carry it just fine, been there done that. We do that for some local long range dives and it works swell. If you clip it off diagonal it's self balancing. Plan to add a few pound of weight to the stage so it's not floating up against you as it depletes.

Do some reading up on independent doubles so you breathe them down in a good sequence to preserve redundancy and have it.

Pete

Another option would be to rent a high pressure steel 120 from the shop at Captain Don's, I think it's Walt's rec tech? That would extend your dive time considerably and you could carry a small pony for a bail out bottle. I brought a 19cf with me last trip for solo diving. Be sure to post a trip report when you get back. I've been considering Bonaire solo as well.
Andrew.

Pete:

Is there a nice little commercially sold kit with everything I'd need at ScubaToys, LeisurePro, Scuba.com, etc...that'd do that? I've never dealt with stage setups and know hardly anything about them.

Andrew:

Yes, ideally diving a single big tank would be great, but by the time I pay a rental fee, & haul it back after every dive to get refilled instead of just swapping other tanks, I figure the expense and inconvenience would be big drawbacks. One of the key advantages of the unlimited shore diving is that 'all you can eat buffet' mentality that says 'It's paid for, I can dive all I want!' Rather than 'Another dive's gonna cost me x amount of money.

Good to know Captain Don's has that option, though!

I've stayed at Eden Beach Resort (WannaDive dive shop) 4 times & Buddy Dive once; planning Dive Hut serviced by WannaDive this time, since I may be solo.

Richard.

drrich2:

Pete:

Is there a nice little commercially sold kit with everything I'd need at ScubaToys, LeisurePro, Scuba.com, etc...that'd do that? I've never dealt with stage setups and know hardly anything about them.

Click to expand...

Sure! Stage/Deco Straps and Hose Retainers by Dive Rite - Dive Gear Express

Agree carrying a stage is the easiest way to use 2 tanks on a vacation trip.

Outstanding! Ian, I think we have a winner. The travel stage strap kit would even save me the hassle of hooking it to the main tank; I could hook it to my BCD via chest & waist D rings. I could simply put a tank banger on & use that to secure the second state mouth piece until needed, and I've already got an old analog SPG so I'd mainly need to buy a 2'nd regulator.

I'm not sure how it'd be back rolling or giant striding off a boat, but I'm aiming for shore diving. And Oil Slick Leap has a ladder (which I've never used to get in, but I guess I could).

The only hassle is apt to be whether to redistribute some of my weights if I clip that extra 80 cf aluminum tank on my left front side. Guess I'll have to see how I sit in the water with it.

Richard.

If it is a standard 80 (not a compact 80) you will adapt with just a few minutes practice. If you can use sidemount bungies straps you can even get it to ride silently next to you instead of like a stage in front. I have not had as much luck with compact 80s slung to one side.

I have found that a slides with D-Ring on the cam bands can often be used as pseudo sidemount points on a BCD that is not a 'proper' sidemount BCD, and that gets the 80 completely out of the way while diving. It is not weight bearing like a BCD with front chest D rings might be , but in the water it's nice to have the tank hide off to the side.

In other words, not a 'proper' sidemount, but using the sidemount ideas to move the tank out of the way underwater is really nice.

ianr33:

Sure! Stage/Deco Straps and Hose Retainers by Dive Rite - Dive Gear Express

Agree carrying a stage is the easiest way to use 2 tanks on a vacation trip.

Click to expand...

I made mine out off odds and ends but that's a nice commercial solution.

Drrich2 for the regulator I use a bungee loop around the cylinder. Repurposing a tank banger will do the same thing, An extra octo holder can stow you primary second stage when not in use.

You can offset a little weight or try the diagonal clip off.

Richard, I would suggest you take a good overall look at your diving technique before changing equipment. Simply adding tank volume is not always the best way to improve bottom time. Sometimes equipment is the answer to a problem but IMO it's always best to solve the problem with technique if possible. Before spending money on extra tanks, not to mention the extra work it involves, I would suggest you dive with someone who can accurately evaluate your diving. One of my main Bonaire diving buddies is just a bit bigger than you are with the same general overall description and he can easily hang with me for 75 to 90 minute dives on an 80. Small changes in weights, trim and diving style can make a big difference in SAC and it's hard for someone to evaluate themselves.....plus many (likely most) divers really don't know what to look for. The one equipment change I would suggest you at least look into would be a good quality set of blade fins as opposed to the splits. I know folks love their split fins but with the blade you can add efficient kicks like the frog kick that are not easily done with splits. The other issue with splits is they are effective with a narrow range of kick styles, it is possible your kick style is not the most appropriate for use with splits, again something that it much easier for another diver to evaluate.


Also, consider your overall diving style. Are you the guy who is always deeper than the rest or do you zoom from one coral head to the next? Locate that SOB in the group that always seems to come back with more gas than the rest and hang with them, maybe they know something you don't. Keeping just a constant depth at the upper range of the group and adopting a slow graceful cruise can do wonders for your sac. In the end, adding tank volume might be the answer but before doing so, it only makes sense to me to remove any inefficiencies in my diving style first.

drrich2:

if I signed up for a PADI rec. sidemount course, grabbed an appropriate BCD & kit, could I run off to Bonaire for the typical 7 day unlimited shore diving package & dive 1 1/2 hours/ dive using 'off the rack' 80 cf aluminum tanks they provide

Click to expand...

The simple answer is, 'Yes'. I have dove sidemount in Bonaire during each of my last two annual trips there. I simply took my sidemount regs, along with my single cylinder reg, and an appropriate BCD. The first time, I took my Nomad, in addition to my backplate. Last year, I just took my backplate, and an OMS Profile, and left the Nomad home - it isn't needed. Each year, I did maybe 6 SM dives during the week (out of ~30), dove single cylinder most of the time, and had plenty of gas for what I wanted to do. I go to Bonaire to relax, and single cylinder diving is fine for me. For most of the shore entries, sidemount will work just fine. For some of them, I actually walk the cylinders into (and out of) the water, one at a time, to get past the slippery areas right at the entry point- a couple of them can be a bit tricky with a single cylinder on you back, I wouldn't want to do it with two 80s hanging on me.

drrich2:

or is there more that I'm missing?

Click to expand...

In terms of being able to dive SM in Bonaire with the ubiquitous AL80s, no. I would definitely support your stated intention to get some training before doing so, however. Yes, a lot of divers come to sidemount in a do-it-yourself mode. But, many of them do that coming from a backmount doubles, technical diving background, and the transition is therefore relatively easy. I was used to having a lot of gas on my back, was used to slinging stages / deco bottles, making gas switches, etc. What I sought initial advice on was optimal methods of rigging the cylinders for SM, and the best way to set up my regs (hose lengths, etc). After that, I did a lot of 'trial and error' work until I settled on what was best for me. In taking a SM course (such as the PADI reccreational sidemount course you mentioned) you SHOULD get a good foundation in rigging bottles, AND in managing two independent cylinders, AND in setting up your regs.

drrich2:

Is swapping out tanks a big hassle?

Click to expand...

Not at all, depending on how you rig them. If you use typical stage rigging, with a screw clamp on the bottom, it might take a little longer. I use cam bands for the bottom attachment points, and changing them from one tank to another is very easy.

drrich2:

Do sidemount divers often use manifolds to connect 2 tanks to make one functional unit

Click to expand...

No (generally not).

A final thought - I would actually echo Herman's comments on this one. Yes, you can do sidemount in Bonaire - I find it is easier than doing backmount doubles there, simply in terms of gear availability. And, with 160 cf of gas, you can stay down a LONG time at 50-60 feet (in terms of gas supply; NDLs are a separate issue). But, the solution to your goal - longer dives - might be found in technique as much as gear.