Hello all. I recently got my hands on a keg for a fairly good price so I went ahead and got it. I have been making root beer using the Zatarain extract, following a recipe effectively the same as on the bottle. In the past i have been using yeast to carbonate in bottles but am now trying to use CO2 with the keg. I have read tons of forum posts and have tried carbonating at anywhere between 25-30psi in a 37°F fridge. I have allowed the keg to sit for over a week in this state. I then connected 25' of 3/16 ID hosing to the outlet as many posts suggested either turning down the pressure for serving or using a LONG serving line. However, even under these conditions, my root beer comes out flat. The instant it leaves the serving line and touches the glass (tilted or not) all of the foam comes out and I am left with a flat (or mostly flat) soda. I have no clue if this is due to overcarbonation of the root beer, using too long of a serving line, or some other factor. I am very new to kegging so I have been trying to find my way around this issue for a bit. Any help would be appreciated and I plan to check back regularly if any more info is needed.