I got a Draeger 45 min/6.8l SCBA tank off ebay for about $95 shipped, and it passed hydro.JoeB's stuff is good but he needs to move out of Cali because the prices are way too high for me.But yeah, I want a guppy tank since I don't hardly ever have a chance to do enough shooting in 1 day to drain more than a small tank. I mostly wonder if that Hatsan tank is decent enough, it would be about $45 or so shipped after my Amazon credit.