If you plan on playing alot then the investment for some large scuba tanks is well worth it. but it does take some time to pay for its self. You can fill them from the firehouse but you need a special adaptor and they are hard to find. (I had a hard time finding it) I still dont have one but my friend does

If you only plan on filling your own tanks then one scuba will do for a day of medium play, the psi will be less after each fill, but i find i do just fine at the end of the day with 2k psi fills.

I personally use 2 80cu 3k tanks to fill my tank, i go from one to the next always in the same order so you save psi in the tanks, then after those 2 i top it off with a 120cu 3.5k tank. with the 3 tank fill method i find that i get ruffly 12-15 fill at 3k way more then i need in a day. So what i do is charge my friends a $ or 2 to use my air for the day. after a year i have 1/4 of my expense for the tanks paid off.

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I get asked "Why?" alot. Why do you do this? Why did you do that? Why would you think of such a thing? WELL HERE IS MY ANWSER..... BECAUSE I CAN!!!!!!