I recently purchased a new burner and 10 gallon stainless kettle to get into all grain brewing. The new kettle is a brand that has a good reputation. I did a test run with a few gallons of water, just enough water to cover the thermometer probe just to make sure that there were no surprises on my upcoming brew day. After I tried it out I put it away without taking out the thermometer and valve. A few days later I took it out to get ready for brewing the next day and I noticed both of the welded ports had rust in the threads. My question is if everyone normally removes the thermometers and valves after every use? I never had any rust problems with my old kettle that has weld less fittings.