Starting sidemount and tanks?

I want to get into sidemount diving and I'm slowly accumulating gear for this venture. I want to dive the LP95s but I'm coming to the conclusion (even when I added a aluminum BP) that I am just too negative. I have a couple steel 72 that are matched (I hope) that I will try. I'm going to dive one of my 72cf tanks with the aluminum bp. I'm a little negative, but I suspect that I won't be with the aluminum plate. Now this is all with a 3/2 suit mind you. I will dive dry when it is cold enough, and I suspect the 95cf tanks will work with the drysuit. But we shall see.

What brand LP95s are you looking at? And what rig are you considering?

I currently have two Faber LP95's and a couple Dacore LP72's. As far as rigs, I'm looking at the OMS profile adapter. I'm not a big budget guy and my wife is giving grief on what I've spent already.

I just looked back at your OP and noticed the BP part. That will be an issue, especially with the 95s and a 3mm suit. What size wing do you have?

I'm diving a 32lb hog. I've been thinking about going with a 5mm so that might help.


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With a 3mm and steels, even with a 5mm, you will likely need more lift than 32lbs. A 7mm might work, but you might still have issues at depth when the suit compresses.

I'm tracking. I have a friend that has an OMS wing he will sell me. I'll have to check it. I think it is a 50lb lift.

32 pounds of lift is not a lot of lift for anything other than AL 80s.

Steel 72s vary a bit as everybody made them and not all are the same, but in general a pair of steel 72s with valves is about 14-15 pounds negative at the start of the dive. Add another couple pounds per reg, along with your 2 pound back plate and you're looking at 20+ pounds of negative buoyancy before you add in lights, reels, the rest of the harness, etc. Adding a stage and a deco bottle would not be an option.

I'm not sure a 5mm will help. I dive both a 5mm and a 3mm with an without a hooded vest and I just don't notice that much difference, although my 5mm has been on enough 180'-210' dives that it is probably closer to a 3mm now anyway.

As for 95s I dive a Nomad and it's nominally a 60 pound wing, although Lamar estimates it drops to closer to 50 pounds when fully inflated on the diver, given the constraints on the wing to keep it in position, and I think it closer to 45 pounds by the time you snug up the bungees to limit the gas in the front portion of the wing, plus I dive a dual bladder Nomad and that probably costs me another 5 pounds of lift due to the extra bulk in the same external shell. If I dive cave filled LP 95s and a stage with a 3mm or 5mm wet suit, I have to take care as it will be a couple pounds negative at the start of the dive with the wing trimmed the way I prefer - I end up having to loosen the bungees under the wing to let it inflate a bit more.

The point being that if you're trying to float a pair of cave filled 95s with a 32 pound wing and a dry suit, you're probably going to end up with more gas in the drysuit than you really want, as it's going to be a large bubble to manage.

Gotcha. I think I'll start on the 72's FWIW. They are both dacor tanks, and I'll check their buoyancy before I get all jiggy with them.

DA Aquamaster:

32 pounds of lift is not a lot of lift for anything other than AL 80s.

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Not quite true. My Armadillo is rated with only 32 pounds lift and I dive it with Worthington 85s and Faber 95s with stage cylinders all the time. But I'm in a dry suit. If I dive wet I use smaller cylinders or my Nomad (original with 50 pounds rate lift, closer to 40 the way I have it rigged).