Question for steel tank aficionados

[Brent Bowman]

I have been using HP 100 steel tanks for awhile and think they are the greatest thing ever. I have been thinking about adding another steel tank to the fleet and was thinking maybe a HP 117 ? So what's it like to swap back and forth between a HP 100 and a HP 117 just based on personal experience? Am I going to have to change my weighting much to swap back and forth between the 100 and the 117? I use about 6 lbs of weight now because we mostly shore dive and I like to be able to swim back in to the beach underwater with not much air left.

Thanks for input on using a HP 117 steel tank.

Thanks again,
Brent Bowman

 

[Divin'Papaw]

I have been using HP 100 steel tanks for awhile and think they are the greatest thing ever. I have been thinking about adding another steel tank to the fleet and was thinking maybe a HP 117 ? So what's it like to swap back and forth between a HP 100 and a HP 117 just based on personal experience? Am I going to have to change my weighting much to swap back and forth between the 100 and the 117? I use about 6 lbs of weight now because we mostly shore dive and I like to be able to swim back in to the beach underwater with not much air left.

Thanks for input on using a HP 117 steel tank.

Thanks again,
Brent Bowman

The biggest pain is not the weighting difference but rethreading your cam bands with each change. HP 117s are 8” diameter tanks and HP 100s are 7.25”. Doesn’t seem bad but believe me, it becomes a PITA. Stick with one diameter tank. You’ll be much happier.

 

[Brent Bowman]

The biggest pain is not the weighting difference but rethreading your cam bands with each change. HP 117s are 8” diameter tanks and HP 100s are 7.25”. Doesn’t seem bad but believe me, it becomes a PITA. Stick with one diameter tank. You’ll be much happier.

Thanks for the input, I don't think expanding the strap and cam lock to fit an 8" tank will be much of a problem with the way my Aqualung BCD is set up but I might be missing something?

Another question I thought of is how much heavier will my overall gear weight be with the HP 117 versus the HP 100? The 117 tank weighs a little more and if I have to add lead weight might become an issue? Carrying more weight up and down and across the rocks here isn't a good thing.

Thanks again!

 

[passedoutwookie]

Big thanks to @tmassey for putting the attached tank spec sheet together. Save it and you will never need to guess what the difference between two tanks will be.

I use 100s and 117s. It is a bit of a pain to adjust the cam bands, but takes no more than 2-3 minutes. Not that big of deal unless you’re in a small boat or in a big rush. Mark the cam bands for each tank and there’s no trial and error to get it right.

I love my 117s.

 

[Eric Sedletzky]

I have a steel 100 and a steel 120.
I swap no problem without having to add or subtract lead. The 7-1/4” diameter for both is nice.
I don’t personally care for 8” tanks.

 

[Bob DBF]

I have a steel 100 and a steel 120.
I swap no problem without having to add or subtract lead. The 7-1/4” diameter for both is nice.
I don’t personally care for 8” tanks.

Depends on which tanks. Between my HP 100 and MP 120, I really need to drop that 6#, to make the walk to the water if nothing else.

I'm not a fan of 8" tanks, they make me feel top heavy. I picked up an LP 95 cheap, and used it down south on boat dives, i always got a healthy fill.

 

[Eric Sedletzky]

When my 120 empties out I think it’s lighter than the 100 in the water. Same wall thickness but bigger air space.

 

[Endler's]

Aqualung BCD

If your BC has Griplock band, then velcro has 8" & 7.25" preset markings, making adjustment easy.

Faber 117 adds 5 lbs. (tank + air) to your land/carry weight. Difference in buoyancy is one pound.

 

[Brent Bowman]

Thanks for all of the great info! I realized that I know somebody local that has steel HP 117 tanks that will probably let me try one of them out so I can see for myself how I like them in the water. Hope I like them because I like the way they look on paper.

Thanks again,
Brent Bowman

 

[happy-diver]

Cam bands seriously, I used to be scared of cam bands, you can't get them properly tight, without removal from the last two slots anyway for a good pull and feed you should learn them backwards

Would be a legit padi course