Hey new AG brewers: Don't make my dumb mistake. I made my first all grain 3 batches ago. It had it's issues but i chalked it up to me learning a new process. second batch went better but I has an inorganic medicine taste going on. The third batch was a repeat of batch #2's recipe. I nailed everything. Mash temp, OG, you name it. After 6 weeks of fermentation and conditioning I opened a bottle. Still that medicine taste! What happened??? After some accidental reading, I found out I was incorrectly using a low temperature racking hose to transfer hot wort to the kettle.
So I set up an experiment. I ran hot water through the hose, then poured a control into a cup that had not been through the hose. Sure enough, the hose was leaching off a terrible medicine flavor into the water. I read everything when I built my mash tun. I never saw that I needed a special high temp hose. Oh well, I was almost ready to quit. Don't do what I did