I use this stuff everywhere in my system, after each brew day I remove it, clean and replace for next brew day. I noticed the tape in the keggle seems to turn sorta clear, maybe from the high temps and only on the inside connection. Transfers from Mash/Lauter and HLT tanks are done with gravity and the smallest air leak will prevent good suction and stops me from hitting the volumes I have set up in my software. If it has threads, it gets tape. In theory, no wort should touch the tape, it should be all on the inside of the pipe, not the threads. The only real place of concern is inside the keggle, I have a connection to the dip tube/strainer. Those threads are exposed inside the keggle and those are the one that end up clear.