Every once in a while, I don't know it it's an adjunct I've added or just dumb luck, but occasionally, I get a stuck sparge. Since I often don't mash out, this can mean unintended continued conversion (I effectively ruined a beer this way). The first time this happened, I turned off the valve, stirred things up, waited to settle, vorlaufed, and tried again, and got stuck again. After that I just stir and give up the idea of clear wort into the boil kettle. Is there a way that works better? The only thing I can think of is keeping rice hulls on standby.