I’ve been all-grain brewing for several years now. I had a 48-qt Igloo Cube with a circular braid in the bottom. I wanted to make some heavy brews and possibly 10-gal batches so I made a new tun from a Coleman 70-qt Xtreem with a long braid running it’s length. I made 3 brews in the new tun without any issues. Yesterday I made NB’s Brickwarmer Holiday Red All Grain Kit and after mash-in it stuck mid-way. I think I had the valve too far open. On the batch sparge I lessened the flow rate and drained almost every drop of wort. I was thinking the new tun has a larger valve and capable of flowing much more liquid. This made me wonder is there an optimal flow rate?