That's really the only way....we all do it...and I've never heard anyone say they felt their beer was ruined because they opened the bucket to take a reading...
Remember there's a cushion of co2 protecting your beer. Just be conscious of how/where you set down your lid while drawing your sample...or better yet have someone help you. Sanitize both sets of hands, have a friend open the bucket...drop your theif or turkeybaster in to draw a sample, then have friend slam lid down... Should be able to do it in less than 30 seconds.
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
I gotta tell ya, just between us girls, that Revvy is HOT. Very tall, gorgeous grey hair and a terrific smile. He's very good looking in person, with a charismatic personality... he drives like a ****ing maniac! - YooperBrew