Steel tanks

[Rekcals83]

So I've had a couple of steel tanks sitting in my closet for years, since the places I've dove at I have flown to.

I was wondering if there is anything that could be wrong with the air in the tanks after sitting that long?

Also, if I ever wanted to convert them to nitrox tanks what would the best way to go about that be?

 

[Compressor]

Converting them to nitrox involves having them oxygen cleaned if the provider of nitrox uses partial pressure blending to fill the tanks. If there is a premix-ready option, no cleaning is required.

Since your tanks are out of VIP, they need to be VIPed anyway. If the tanks have rust inside of them, there is a possibility of less oxygen in the tank as it was used during the oxidation process. If there is no rust, the air is fine.

 

[Rekcals83]

Are those things I can do at my local dive shop? what kind of price range am I looking at for 100s?

 

[rob.mwpropane]

Singles VIP, hydro, and fill around here is $55 or so

Hydro is about $30-35, so without it VIP and fill would be $25 or so.

You could get them them O2 cleaned, no idea what that runs. As stated by @Compressor, depends if nitrox is banked or partial pressure blended at your LDS.

 

[Jim Lapenta]

Depending on where you are I've seen O2 cleaning charges vary widely between 25 and, in once case up, $75. Usually 40-50 is the norm.
Another thing to consider is do you really need nitrox for your local diving? If you're not regularly diving beyond 60 feet doing more than 2 dives a day, I wouldn't mess with it. It doesn't provide that much of a benefit in my opinion.
Our local quarry is 45 feet deep max. Nitrox there is not at all necessary.
When I go to deeper spots I have to decide if using it is required. Often it's not because I'm not against carrying a stage of 50-100% and doing deco to be safer. And I won't do more than two dives beyond 80-90 feet per day. No desire to do more than that.
If a shop is banking nitrox up to 36% and they want you to have O2 clean cylinders, find another shop and dive air. If they do partial pressure, then yeah, the tanks and valves need to be O2 cleaned.