This is what I do. Works great. I usually put the keg into my kegerator for a day or two under serving pressure to allow it to chill. Then release some pressure, hit it with the gelatin and then crank the pressure to 45-50 psi for 12-18 hours. After the burst carbonation, it’s ready to drink, although it won’t be crystal clear for 2-3 days. Then you can watch TV through it.I use a 0.5L PET bottle with a Carbonation Cap and a small piece of hose.
I fill it with water and gelatin, then lightly loosen the Carbonation Cap and run some CO₂ through the bottle to scrub out any air.
After that, I pressurize the bottle to a higher pressure than the keg.
Using a jumper hose, I inject the mixture into the keg.
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