If you're talking paintball tanks most sporting goods stores that sell the guns refill them, I've also had luck at farm supply stores. If you're talking tanks like for beer or refilling paintball tanks then go to a welding supply facility like airgas
For CO2 tanks for beer dispensing check beer crazy in clive/urbandale or Fessler Carbonic on E Ovid in Des Moines. They provide CO2 for the food/beverage industry. You don't want to use the CO2 provided by fire stations, welding housed, or paintball companies, there is a difference. Most home brewers that are into kegging in the Des Moines area use one of these two sources.
For CO2 tanks for beer dispensing check beer crazy in clive/urbandale or Fessler Carbonic on E Ovid in Des Moines. They provide CO2 for the food/beverage industry. You don't want to use the CO2 provided by fire stations, welding housed, or paintball companies, there is a difference. Most home brewers that are into kegging in the Des Moines area use one of these two sources.
I'm not trying to be a jerk, but.... I have been in the Welding Supply/Gas Distribution business for just short of 20 yrs.! That being said there is absolutely NO difference in the Co2 being put into a "welding" cylinder or a "beverage" cylinder and at the majority of the distributors there is no distinction between the two. One coming back from a welding shop today could be refilled and delivered to a restaurant tomorrow.
Both product comes out to the same bulk tank and manifold that is filled by the same bulk tanker that fill the welding distributor, fire extinguisher service center or dry ice manufacturing facility. I would not recommend buying into the whole "food safe" marketing ploy. When was the last time you have heard of someone becoming ill from contaminated Co2, literally millions of people consume it a day in the US alone.
I to have worked for various industrial supply houses since the 80's, including one that is now owned by Praxair, if your've heard of them. There are two main types of CO2 used in the industry beyond what is used for medical, "Beverage Grade" and then everything else. The difference between the two is that beverage grade CO2 has less TRS, and HC, gasses in it, such as H2S, CS2 ect... if you want stinky (farty smelling) beer use whatever you want, I've been down that road before and have been brewing for 20+ years.
Not sure if anyone is going to read this because it is a old thread but here it goes anyway. I recently purchased a Kegerator and wanted to know where I could get the co2 bottle that came with it filled. I ran across this thread the other day and went to Beer Crazy in Clive/Urbandale. The gentleman at the counter when I asked him if they filled co2 said no they did not. I then asked him if he knew where I could get it filled, he said there are a few places in the area and you can find them in the yellow pages. Well that response turned me off to any future business I might have done there.
I ended up going to Fessler Carbonic on E Ovid in Des Moines. They were friendly and took almost no time to fill my co2 tank. The fill cost me under $15. The guy that fills the tanks leaves at 2pm so get there early if you want your tank the same day. Hope this helps someone in the future.
Oh and the place by Orlandos pizza is closed and boarded up.