Fish Eye Bubbles in Foam

[d_striker]

We brew on a 5bbl system. We carb and serve from brites and keg when we need to free up the tank. I carb using gitchegumee's carbonation method and let the beer settle for a couple of days before serving. Our young tank beer never wants to form a good head out of the gates, even though it seems like there is a lot of CO2 in solution. What head does form is laden with big fish eye bubbles.

After pouring off a couple of bbl's, the fish eye bubbles go away and it starts pouring with a nice tight creamy head that leaves proper lacing. After kegging, the head improves even more.

At first, I thought it had to be residual acid or saniclean in the tanks or caustic in the beer lines. After thoroughly evaluating our cleaning processes, I'm pretty certain it's not chemical residue.

What's going on?

[gitchegumee]

Could it be...

possibly that your lower levels of beer are not getting carbonated properly? Perhaps the lower parts of your tank are stratified, leaving the upper levels nicely carbonated, but not below the stone. Can you get the tanks colder after carbonation? This might roll the beer due to temperature gradient and mix your beer.

[d_striker]

possibly that your lower levels of beer are not getting carbonated properly? Perhaps the lower parts of your tank are stratified, leaving the upper levels nicely carbonated, but not below the stone. Can you get the tanks colder after carbonation? This might roll the beer due to temperature gradient and mix your beer.

That's a good hypothesis. I believe the beer going into the brite is between 38-42F depending on how full the FV was. Our walk-in cooler is about 36-38F. I carb using your method and I believe the beer get's slightly colder as it sits in the brite over the next few days. I don't have thermometers on my brites though.