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What is the benefit of having steel tanks in cold water?

total weight on land is significantly lower for gas capacity carried. A LP72 is roughly the same size as an AL80, but your total rig weight on land is going to be almost 10lbs lighter for the same amount of gas. If you look at a HP100, you have a tank that is 2lbs heavier on land, but holds 25cf/30% more gas, and has a 6lb buoyancy advantage. Net result is 2lbs lighter rig to carry when full, 4lbs when empty, and you get 30% more gas to use. Doesn't make sense to dive aluminum tanks in cold water
 
What is the benefit of having steel tanks in cold water?

To give you concrete numbers:

Luxfer AL80 holds 77.4 cubic feet of gas. When empty, they're 4.4lbs positively buoyant (floaty). They're 31.4lbs on land.
PST E7-100 holds 100 cubic feet of gas. When empty, they're 1.0lbs negatively buoyant (sinky). They're 33lbs on land.

If you go from a Luxfer AL80 to a PST E7-100, you get 30% more gas and you can take 5.4lbs of lead off your weight belt....but they weigh an additional 1.6lbs so you're carrying a net of 3.8lbs less weight on land.
 
I wouldn't buy anything Chinese when it comes to an HP container. I'd also buy steel tanks, never AL again.
 
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I wouldn't buy anything Chinese when it comes to a HP container. I'd also buy steel tanks, never AL again.

If it has the DOT certfcation, I might be tempted. But I do not know of any tanks made in China that do.

Shop around locally. Some local shops may offer free fills (10 or up to a year) which will have a big effect on the value.
 
If it has the DOT certfcation, I might be tempted. But I do not know of any tanks made in China that do.

I have nothing but BAD experience with Chinese products, services and business. Even if it had DOT, I still wouldn't buy it. I rather spend my money with US companies that I can trust more and I know I can go after them if they violate standards or laws in the US. Cheap is just that, CHEAP and Chinese cheap is CRAP!!
 
I have to agree with
BurhanMuntasser as far as buying anything Chinese made dive gear, I bought a few dive lights on ebay Chinese made and they were pure garbage-one broke after first dive and 2nd one broke around 10th dive.I would never take a chance buying Chinese made tanks, if there are any impurities in casting of alum. tanks this can result in weakening of thinnest parts of tank-which in tread area which would lead to tank not passing hydro every five years..
 
I have nothing but BAD experience with Chinese products, services and business. Even if it had DOT, I still wouldn't buy it. I rather spend my money with US companies that I can trust more and I know I can go after them if they violate standards or laws in the US. Cheap is just that, CHEAP and Chinese cheap is CRAP!!

I usually don't agree with general blanket statement like this, but for high pressure metal container, yes, I won't either. Fror dive light, backplate, BC, or even regulation, maybe. But anything that can kill you, definitely not today. Not yet
 
I would never chance diving with a regulator made in China, I do not know of many divers who would disagree with me..
 
I would never chance diving with a regulator made in China, I do not know of many divers who would disagree with me..

Chinese manufactured? or Chinese brand? If it is the former, you may already been using them. What isn't manufactured in China these days
 
https://www.shearwater.com/products/perdix-ai/

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