A couple more basic SCUBA questions...?

Question

What kind of regular maintenance is involved when I buy a full scuba kit (including tank)?

If I decide to buy a tank, should I go aluminum or steel? I will be diving primarily in cold, fresh water lakes in canada, and doing perhaps two tropical ocean dives per year, if that matters.

Most of the dives in the large lakes near me are between 50 to 120 feet deep. There are one or two that are approaching 200. I have only gone for 4 dives so far, at 40 feet deep in clear tropical water, what is a safe depth for me to tell the divemaster I am comfortable with?

As I progress, I would like (of course) to attempt the deeper dives, does this mean that I should have equipment that is Nitrox compatable? Is Nitrox used for shallower (50 ft?) dives?

Has anyone heard of TriMix gas? I'm having a hard time finding info this...

Thanks very much for all the earlier answers guys. Went diving the first time down in Cuba a month ago, and I see scuba tanks in my sleep now! Any additional tips?

Answer 1

I'm a Great lakes diver, just north of Toronto, so may be able to help.

Your regular maintenance includes at least a yearly service on the regs, a yearly visual inspection of the tank and a hydro test every 5 years or less. You also visually inspect and physically test various part of your rig, prior to each dive. For example, ensuring dumps work, LP inflater works, air is on, gauges working, no HP or LP hose issues and a host of other rig specific things. This you'll learn on your course and when reading the manual(s) for your particular gear rig.  Given what you've told me here, I'd start with just the Alum 80's. They're cheaper. Steel has a heck of a lot more neg buoyancy and right now...you don't want that. The type of tank you purchase will have no bearing on what you'll use for your vacation trips. Airlines prohibit tanks on aircraft, you won't be taking them with you on those two vacation trips you hope for. You'll be renting them at your destination.

  Safe depth? That's up to your comfort level and your level of certification. For your OW, you won't be going below 60 feet at all. Ever. Not until you progress up the cert chain. Most OW classes seem to take place at 30- 40 feet. After that, it's up to you if you decide to go to 60. Bear in mind, that most of the wrecks around here are fairly busted up by ice and storms, that lie at 60 feet or less. The gems lie a little deeper, which you'll need your advanced to see. Nitrox isn't a necessity for diving around here. It's a luxury and nice to have is all, for some of the wrecks that lie in an intermediate depth. Ones like the Forest City or Arabia, you won't be using Nitrox on anyway. You can easily exceed O2 tox on even a 32% mix since the Arabia lies close to the theoretical Nitrox depth limit and the FC at the stern exceeds it  and..believe you me...you won't be wanting to spend extra time there. The cold will start to get you.

Tri Mix you aren't going to get near unless you go seriously tech. That's still a long way off for you. It's a hypoxic mixed gas ( less O2 content than normal air) that's used for serious tech dives.

Equipment wise:

Buy what you need for your immediate needs. Rent what you haven't bought. There's really no point in spending a lot of extra cash right now. If you take your diving further you can always sell what's no longer appropriate for your skill level and purchase what is.

If you plan on doing most of your diving here, I'd actually start spending ( besides your basic rig) on exposure protection. Mid summer here, diving Tobermory, the temps can drop to 40F in places. Even a 7mm double suit will leave you a little chilled after 30 minutes in the water. You may want to save up for a dry suit, take the course and use that as a primary source of exposure protection here. It'll make that second dive of the day easier on you.

Answer 2

Your open water diver certification class should cover basic equipment maintenance.  The most important thing you can do yourself is thoroughly rinse all your gear after every dive outing.  This is even more important in salt water, but even fresh water can introduce debri and organisms into your gear that is best rinsed away!  

There are specialty classes available that can provide advanced gear maintenance and emergency repair training.  If you dive regularly in remote areas this is probably good training to get.  But if you are diving within dive shop driving distance and at resorts its not really necessary.

Regulators & BCs should be serviced yearly.  Tanks inspected every 5 years.  The most common sport-diving tanks these days are aluminum.  I dove with steel 90s for many years and really liked them, but the aluminum tanks are a bit lighter and easier to haul around.  

NITROX is simply air with a higher-than-normal oxygen content.  You need special certification for this, but the only special equipment would be tanks specifically marked for NITROX use.  Other gear, including the regulator, should be the same.  Nitrox Diving does not allow deeper dives, and is used essentially the same as regular compressed air diving.  Its main advantage is allowing longer bottom times and decreased surface interval between dives.

Recreational (Sport) Diving is usually limited to depths of 130 feet and less.  Those deeper "200 foot" dives are extremely hazardous with sport diving equipment and unless you have received special training should be left for the professionals.

TRIMIX includes a large percentage of helium in the air mix and is used for professional diving, not sport diving.

Always dive with a reputable organization.  I was a member of a very good dive club through a local college that was well run and had two dives every month.  If you have a similar organization near where you live I would highly recommend joining.  A great way to meet fellow divers, too.

Answer 3

You have to get your tanks serviced, to make sure that they arent rusting. I also know that you have to get your regulator rebuilt every some odd years.

if you get a tank, i would get aluminum. It helps me more with boyancy, because im rather small.

being open water, you can only go a max of 60 feet. If you want to go deeper, you need to get nitrox, it helps with decopression, and as far as i know, to get a nitrox tank filled, you have to be nitrox certified. You can use it at shallower dives, thats all i ever breathe.. and as far as i know, there isnt anything you have to do to make it nitrox compatible.. and you can get your tank switched, so you dont have to worry about buying a new tank. Trimix gas is for people who are planning on going deep for a long time, and is usually used by cave divers. Its not necessary for dives 100ft and under, or open water dives. Im 18, and cavern certified... all i ever dive in is fresh water springs, but ive been diving since i was 12.

I hope that i helped!(:

Answer 4

I prefer steel tanks since they last forever if cared for.  Aluminum tanks can only be hydro'd 3 times and then that's it for them.  Also steel is either negative or neutrally bouyant.  Compare a steel, high pressure "100" with a aluminum 80 for size comparison.  

I get my breathing equipment (regs) inspected every year and overhauled every two years.  It's your lifeline, treat it well.

Tanks used for Nitrox need to be cleaned specially for a higher concentration of O2.  Also, EAN doesn't allow you to go deeper--it allows you more NDL bottom time at a given depth (compared to regular air).  

Trimix is air in which helium is mixed in to replace some of the O2 which is reduced because at a certain depth, 21% concentration of O2 becomes toxic.