Hi, me and a friend are poor students so decided to have a bash at home brewing, we went to a local super market and got a cheap kit (brew buddy).
Just started to drink our second batch and we've got the same problem, our larger is flat. After the first time was flat (but tasty enough) we made doubly sure the cap and o-ring on the pressure barrel were lubed up with vaseline, but its still gone flat.
We have seen for sale CO2 injectors for the top of barrels, but thought they were extras and not necessary (as our home brew larger kit didnt come with one).
Any advise would be great.