My local brewery fills growlers all the time. They just fill them up till theres no airspace in the top. They last at least a few days in the fridge. (maybe more, but I don't know because they're empty by then)
Secondary #1: Mead Experiment
Secondary #2: Welch's Wine Experiment
Kegged: Organic APA, Kick the Bucket APA, Pub Ale, Argentine Cascade IPA, ESB
Bottled: Wild Raspberry Cider, Cyser, Insane IPA, Lady Bug Pumpkin Ale, Cider, Christmas Cider.
RIP: Raspberry Hefeweizen, Hoppy Lager, California Common, Oktoberfest, Hefeweizen, Melted tubing brown ale, Honey blonde ale