Question Sidemount in warm water?

[robbiny]

While everyone is hanging out with their BCDs in the racks I've got my rig on (it weighs nothing so why not) with my tanks set-up.
When everyone else is starting to gear up I've got my left tank on, I've got the right on before they are done. Then I'm off the boat.

This is awesome. Thank you so much. I noticed the same from our dive master though it was in the jungles pretty hot

 

[rongoodman]

I was told by aggressor that they do not permit double tank dives in any shape! I asked as I’m diving with them in Egypt in November (booked before I knew they wouldn’t allow SM). Their response was simply “we only permit single tank dives, you’re more than welcome to dive sm with a single tank”.

I was surprised to have a young guy diving SM doubles with us a few years back on the Aggressor Okeanos II out at Cocos Island. Every dive is a back roll off a RIB and a number require negative entries. He did well with it though.

 

[LFMarm]

If you’re diving stages in rough sea SM is no harder than BM imho as you still have to kit it all up on the boat and roll off / waddle to the back, however if you’re doing non-deco on rough sea and you need negative entry then BM is probably better, unless you are truly an expert SM diver like Tomasz Michura who makes it look easy!

You are certainly right that experience and repetition will make anything easy. For me personally is pretty uncomfortable to set up 3/4 tanks in sidemount as the boat is rolling. These situations however are pretty rare. 95+% of the times I am able to donn all tanks in the water which is easier for me than walking off with a set of doubles.

 

[Bump_Head]

I was going to scroll on by but figured my perspective is slightly different than what has been posted.
Yes, sidemount is a tool, however it’s a tool for more than just cave diving. I travel the world currently full time, with my diving gear. It’s used for both recreational and technical diving. Sidemount equipment suits the requirements.
Not sure about the postings regarding being slow to drop. The rig is already on way in advance and it’s only a matter of clipping tanks. On particular cattle boats I’ve popped a reg in my mouth and ran off the back, clipping the tanks on descent. Negative entries are just as easily done as with any backmount system.
People mention multiple tanks on rolling seas….fair enough but if I’m clipping multiple tanks I’m most certainly on a tech boat and everyone is having the same issues.
Lastly regarding the extra work for the boat crew: I am the customer and if they do not wish to accommodate me sidemount diving, then my dollars will be spent in the shop down the beach, so to speak.
Remain open minded in regards to logistics. I have left my personal gear behind and utilized local rented equipment in locations that warrant that approach.
Peace be the journey

 

[autrichon gris]

I’ve seen one side mount diver on 20+ liveaboard trips. Not worth the hassle for the dives you’ll be doing on them.

I am practising one side sidemount in the Red Sea for example. The Red Sae is very salty, no problem of balance with aluminium tanks.

 

[LFMarm]

I am practising one side sidemount in the Red Sea for example. The Red Sae is very salty, no problem of balance with aluminium tanks.

As you breathe them down you will eventually create an unbalance equal to the weight of the gas removed from the tank (assuming your tank is perfectly balanced at the start).

 

[autrichon gris]

As you breathe them down you will eventually create an unbalance equal to the weight of the gas removed from the tank (assuming your tank is perfectly balanced at the start).

You're right. I am never perfectly balanced except maybe somewhere in the middle of the dive. At the beginning i am slighyly heavy on the tank side, and at the end slighty lighter. Frankly, i have been diving in the Red Sea like that probably 150 times and it has never (really) bothered me.

 

[rongoodman]

I am practising one side sidemount in the Red Sea for example. The Red Sae is very salty, no problem of balance with aluminium tanks.

That doesn't make any sense. The gas in your tank weighs the same whether you're diving in fresh or salt water. Whether or not the few pounds of weight loss is enough to cause a problem is another question,

 

[autrichon gris]

Sea water is denser than fresh water, so Archimedes' thrust is greater in the sea than in fresh water. Thus, 1 liter of fresh water weighs 1 kg, 1 liter of sea water about 1.024 kg and 1 liter of high salinity sea water like the Red Sea is 1.035 kg. This parameter must be taken into account when choosing ballast. And my tank is a ballast. Ok with that ?

 

[halocline]

Thank you for that. I was really thinking about the same scenario. Practice in open ocean and also be able to go back into the caves. I heard cave divers say it's "uncomfortable" for them to be in the ocean currents. Do you experience similar scenes?

I’m answering this before reading your entire thread, so forgive me if I repeat something already said.

If you are talking about recreational dives on a dive boat filled with recreational, single tank divers, then just use single tanks like everyone else. It’s MUCH more convenient. Of course there are always people on the internet that will say it’s fine using doubles (SM is double tanks) on single tank dives, but in the real world it’s a pain for yourself and the operators of the boat.

If you love the cenotes (who doesn’t!) then learn sidemount for that environment, and practice your sidemount skills in cenotes and OW shore dives. That’s exactly what I did. On the occasion where I do some rec diving, typically in Cozumel while on a cave trip, I use a single tank on my back just like everyone else. In cave diving, which is the vast majority of my diving, I use SM and stages.

When I did ANDP, I did a few SM dives off a small boat. But those were deco dives, on a boat with tech divers and crew, with stages. And it was not easy to gear up and get everything sorted, and that’s with years of experience diving SM in caves. So….not ideal.

You mentioned currents in SM vs single tank. For sure you are less mobile and more affected by currents in double tanks. You have a bigger profile, even though SM is about as streamlined as you can get with 2 tanks, and quite a bit more mass to move around.

Divers use SM in caves because: 1) double tanks are required, and 2) the cave environment often favors the profile and flexibility of SM, and 3) it’s very convenient to gear up in the water. None of those things apply to single tank recreational diving off a boat.