Another new nitrox diver here!

[Kaamoss]

Hey scuba boarders,
I have a full set of dive gear and logged about 40 beach dives in Laguna / La Jolla after my certification in 2001 until I had 2 close calls with insta-buddies. I've been dry ever since, but recently was bit by the bug and I'm ready to try some new groups where I like in redondo beach for another go around. I just got my regs and dive computer serviced, got a new steel HP 120 tank to replace my old AL 80, and switched my first stage from yoke to DIN. Anyways, I suffered a nasty finger cut / broken bone a week ago and will be dry for another few weeks.

I figured that in the meantime, I might as well get my Nitrox certification. The SDI course / test online is incredibly easy, I think it took me less than 2 hours start to finish. Anyways, just thought I'd share the good news! Looking forward to bumping into some of you in the waters by me in the near future.

As a side note, I've been reading about tank sizes and HP vs LP for nitrox tanks. I'm looking to pick up 2 more used steel tanks for dedicated nitrox use. I'm leaning towards 2 HP 100's, since my LDS has their own pre-mixed EAN32 which I would dive mostly and doesn't require partial pressure filling (which I assume means this makes it easier for them to get it closer to 3442 psi?) Any advice on dedicated nitrox tanks would be appreciated. I{t's been a while since I dove so I'm not sure on my SAC rate, but my last few logged dives I was at about 16 SML (I know, needs improvement).

 

[beaverdivers]

Congrats!

If you are getting pre-mix EAN32, then your tanks do not need to be O2 clean or dedicated to nitrox.

Good Luck & Good Diving!

 

[chrpai]

In the world of Nitrox you'll find there is what the book teaches and what the dive shop requires. (If the compressor owner wants pink pony stickers on the tank, well... )

 

[SeaCobra]

Congrats and good luck in your diving. I have always viewed those 3442 or 3500 psi tanks as "double" fill tanks - in that the fill process creates a bit of heat and the tanks cool down. So, what I prefer is to have a little time for the fill because I want folks hitting the water with a full tank and also getting what they paid for. I fill them, let them cool and then top them back off. Of course this is not always possible, so that means I need to run up over the rated pressure a "tad" so when they cool they are where you need them.

 

[HIGHwing]

Despite the fact that I own a number of HP100s, I'm slowly replacing them with LP95s. Quite frankly, it's just too hard to get good reliable fills at 3442. Either the tank monkey fills them too fast, or the bank pressure is a little short, or we don't have time to fill them just right.

If the LDS can't get an LP tank to 2640 at least you can make dirty looks as AL80s go out the door at 3k. Just sayin'

 

[chrpai]

The LP's are nice that way. If someone hot fills them like 80's you end up right on the money at 2700. And if they give you a nice 3000 fill you got 108cf of gas.

And if you put a DIN valve on it that has a 3500psi sticker you never know what you might get.

 

[Kaamoss]

My LDS is pretty awesome with fills, they do all their EAN32 fills from a bank so I don't need oxygen safe tanks. They also filled my shiny new HP120 to 3600psi hot, which should settle in right around 3400ish... Also, if I had the time, they'd fill, wait for it to cool, then top off. Knowing that, and my SAC rate of about 16 right now, I'm wondering if I'd be better off with a higher volume tank like HP 100's.

Thanks for all the great advice! Also, now that I have my nitrox card do I need to carry that along with my open water card, or can I just carry the nitrox card now?

 

[chrpai]

Nitrox card and credit card is all I used to carry. Austin is such a small town town that I don't need the former and thanks to fill cards I don't need the latter.

 

[Islandheart]

The LP95's are kinda pigs but must agree it's easier to get a regular 2500 than the 3400 reguired on HP100's for a full fill.

Being that you've got a HP120, which is a honkin big and heavy tank, the LP95's should not be an issue for you to handle. Getting a 3000psi fill on those 95 gets you about 114cft, sweet.

The steels normally come O2 clean but it's best to have your tanks ready and Nitrox marked for those times when you must refill at a shop that does PP fills.

You are very very wise to get your Nitrox cert and to use it ESPECIALLY with these larger tanks...

Not everybody can exceed NDLs with a 80, but some can (I have a DM that can stay at 60' for over an hour) doing that on air, is asking for trouble. Jumping up to those large tanks, with air, can be trouble if you are not careful.

So, smart man all around !

 

[Kaamoss]

Thanks islandheart! I think based off of what I'm hearing from you and what I've read on other threads that LP95's are going to work well for me. I want to get two of these used, 02 clean, and only used for nitrox. I'll probably keep the HP120 non o2 safe and switch between nitrox or regular air depending on the dive, until I see a good deal on some used LP95.

I get free air fills at my shop, but a nitrox fill on EAN32 for me is about $15, which is still really cheap. I got the first fill for my tank to take to a pool soon and do a weight check with this new tank. Right after I'm planning on getting a nitrox fill for my first dive with it! Can't wait to get wet.