Large Pony Tanks in Shallow Water ?

[ermaclob]

Anyone ever use large 30 or 40 cu.ft ponies in shallower 15 - 30 feet of water as redundant air when soloing? i know that a 19 cu.ft would be more then enough for that depth, i just want to know if anyone use bigger ones. are they inconvenient for shore diving?

the reason i ask is because i have a 40 cu. ft that i recently got from a family friend. i would like to know if i can be used for the type of shallow water diving i do. i currently don't have a pony when soloing.. soooo.... got to start.

 

[DaleC]

Physically, what would be the difference between diving with one in 20' of water compared to 200'?

The real question is whether it is neccisary or not.

When looking at a piece of equipment I have to ask two questions: What problems does this solve? What problems does it create?

A redundant air source allows me a completely seperate supply of air should my initial source malfunction catastrophically, not allowing me to surface safely otherwise.

A redundant airsource is also an extra piece of gear to lug around and adds a degree of task loading to my configuration. Not much in my case because I am used to it, but it is there, none the less.

At 15-30' will a catastrophic gear failure prevent me from surfacing safely? The answer should be no. From that depth a diver should be able to CESA without difficulty. The only exception being if one is diving in a high boat traffic area, kelp bed etc... where direct ascent may be dangerous.

So I weigh the pros and cons; no real benefit vs additional gear and task loading. At a greater depth these odds will change as a successful CESA becomes more unpredictable. It may also change if I am diving an unknown primary system.

That's just my take on things. You must make up your own mind and be responsable for your own outcomes.

 

[sylpha]

i'm taking a guess here that a 30 cubic feet cylinder would convert to a 7 litre cylinder. I dive with 2 of those all the time and in the range you are talking about (4-10 meters) i would be down all day & still only use one tank.

go for it!

 

[ClayJar]

i just want to know if anyone use bigger ones. are they inconvenient for shore diving?

The only inconvenience is the walk to and from the water. A larger pony will be heavier. Other than that, as DaleC mentioned there's really no underwater difference.

Now, if I'm doing a river dive where I'm sometimes in less than three feet/one meter of water, a larger pony can be harder to deal with, but that's a horse of a different color (a pony of a different depth?). For any "real" dive, no matter the depth, the only considerations are "Does it have at least enough air for what I'm using it?" and "Do I want to carry this all the way to/from the dive?" The 40 would almost certainly be more than sufficient for the first, so as long as you aren't put out by the portage, go for it.

 

[Hatul]

It depends how strong you are. The large tank is heavier in air and will make getting out of the surf more difficult as well as walking to the water. For shallow <60 foot diving I like my 13 pony, but if you're a lumberjack you can manage a 40.

Adam

 

[ermaclob]

i have no issue with the weight to be honest, even though it is made of steel. i was just looking at it next to my AL80's and thinking it was overkill. i mean half the amount of air that's in my main system. Thats like what an hour or so of air if i breath steady at 20 feet.

 

[Jax]

Given that I don't want to become a tank collector, the 30cf and 40cf are all I use.

Besides, training with the same equipment all the time is beneficial in developing muscle memory.

 

[Hatul]

i have no issue with the weight to be honest, even though it is made of steel. i was just looking at it next to my AL80's and thinking it was overkill. i mean half the amount of air that's in my main system. Thats like what an hour or so of air if i breath steady at 20 feet.

If you have no problem with the extra weight, then just set it up and try it. It's an overkill for recreational diving but may be useful for deco diving. You should check the buoyancy characteristics with a reg attached as you'll probably need to take some lead off on that side, assuming you don't plan to pass it off.

Adam

 

[GrumpyOldGuy]

At 15-30 ft, why not use a large pony as your primary tank? I enjoy some monkey diving off my boat in local lakes with a small tank, regulator mask and fins, not much else.

 

[ermaclob]

At 15-30 ft, why not use a large pony as your primary tank? I enjoy some monkey diving off my boat in local lakes with a small tank, regulator mask and fins, not much else.

well yea, that would be a great thing to do. but redundant air was what i was mainly trying to use it for.

ill give the monkey diving thing eventually, looks fun.