What tanks for Doubles? 100s or bigger?

[GTRio]

I am about to buy a pair of steel 100s to double up with plans to take the tech 1 course based on the advice of one dive professional, but the shop I am planning on buying the tanks from insists that I should get the biggest tanks I can if I am going to go tech. I am an average diver with an average SAC rate. we do a lot of shore diving and hiking with our tanks.

Any thoughts before I make my purchase?

Thanks

 

[giles45shop]

Bigger is not always better, especially if you have to walk significant distances. I would talk to your technical instructor about tanks and he can (or maybe already has) given you some advice about the size of tanks for your diving style/location. Your physical size also plays a part in getting a tank which trims out well.

HP100's are a nice size and weight doubles tank. When you get to the HP119's & HP130's, you are talking a fairly significant weight difference. If you can get good HP fills on LP tanks, that opens up another avenue. I dive Faber LP95's, which when pumped to 3500 psi are equal to ~122 ft3 each. But if you can't get anyone to fill them like that, you are better off w HP100's.

Your best bet is to find some buddies who dive doubles and try out some different sizes to see which works best, rather than just buying on someone's advice about what "they" think is best.

I would also see if I could find someone w/ a used set for sale. A brand new set of doubles will set you back a grand +/-, whereas used doubles in hydro and vis are anywhere from $400-700. Certainly there's a risk, but might want to think about it. There's really no service or warranty work w/ tanks, so it's not like you have to go to the LDS to keep them in warranty coverage.

Just my opinion.

John

 

[rustyshakelford]

i dive double 108s and they are heavy. luckily i dont have to hike very far but when you add some deco bottles its a great work out

brett

 

[GTRio]

Thanks for the replies,

I also found this thread helpful: http://www.scubaboard.com/forums/tanks-valves-bands/274722-single-doubles.html

I think the HP100s suit my needs.

 

[SparticleBrane]

Have you considered getting a lot more experience before moving to doubles? With <50 dives you are barely starting your diving career and honestly have very little experience. Too Far Too Fast is very prevalent these days.

 

[crpntr133]

Have you considered getting a lot more experience before moving to doubles? With <50 dives you are barely starting your diving career and honestly have very little experience. Too Far Too Fast is very prevalent these days.

And there seems to be a lot of that going on. There were at least two others on SB with the same dive experience wanting to dive doubles for very weird reasons. I really hope that the other two took some advice.
If all else fails take an Intro to Tech class. You should learn a lot. This was the best money that I have spent on a class.

As far as tank size..most will dive HP100 or close to that size. I have two sets of LP85 and my own compressor so I can get close to 100cf @3000. I also have a new set of Worthington HP100's. I dove Faber LP95's before I bought them. As mentioned before, I wasn't sure that I could manage them either on land or water.

Unless you are doing some really heavy deco or such there is really no need for 130's. Yes there are situations that they would be really nice.

 

[Dtaine]

Have you considered getting a lot more experience before moving to doubles? With <50 dives you are barely starting your diving career and honestly have very little experience. Too Far Too Fast is very prevalent these days.

I don't see how moving to doubles is too far or too fast for a recreational diver. I've done a dive with doubles already and plan on moving up soon.

 

[TSandM]

First off, accept that if you are going to do any technical diving at all, you will end up owning more than one set of doubles. Gear accumulation, once one begins to dive expensive mixes, accelerates horribly.

Second, HP100s are good tanks for dives in the T1 range, and are relatively easy to move around and to walk in. For T2 dives, or for cave diving, larger doubles can be advantageous, but see paragraph 1 Once you get your doubles, you are going to want to dive them a lot, to get your trim dialed in and to learn your valve shutdowns, so having tanks you can comfortably walk into the water is a real plus.

Third, I'm in the camp that says to get your basic skills solidly down before stressing them with doubles. I've watched people do it both ways, and I think it's easier to master buoyancy and trim in a single tank and take that knowledge to doubles, than to do both at once. That said, though, buoyancy control gets easier and easier, the more mass you take into the water!

 

[SparticleBrane]

I don't see how moving to doubles is too far or too fast for a recreational diver. I've done a dive with doubles already and plan on moving up soon.

Because most divers don't have the skills needed to correctly dive doubles, especially those with <50 dives.


I did my first doubles dive at dive #40 using a borrowed set of LP95s. I was lucky at the time; my buoyancy and trim were good enough that I didn't have any issues. I kept borrowing them for quarry diving over the next few weeks and got in a few more dives with them.

Then I stopped -- and went back to singles for another 60-70 dives, before I had my own set of doubles. Why? I wanted the experience before I moved up.

 

[rjack321]

I am about to buy a pair of steel 100s to double up with plans to take the tech 1 course based on the advice of one dive professional, but the shop I am planning on buying the tanks from insists that I should get the biggest tanks I can if I am going to go tech. I am an average diver with an average SAC rate. we do a lot of shore diving and hiking with our tanks.

Any thoughts before I make my purchase?

Thanks

Slow down and go recreational diving.

Find a different shop.