I've reutilized from commercial beer. They are 600ml. I've washed them prior to bottling with regular detergent. Then, on bottling day I filled them with Iodophor solution, waited a few minutes and bottled. Obviously the priming sugar fed some kind of contamination that was in the beer. I don't think the problem was the bottle, since I' ve been doing this way for some time and never had problems. After fermenting was done, I noticed a subtle smell of fish, but there was nothing wrong visually so I decided to continue anyway. Also it's worthy noting that during bottling and racking some members were infected with a flu virus, although they didn't really do anything. This is the first contamination I had so I don't really know what to do. I'm probably dumping the batch