Recipe link is here: https://www.brewersfriend.com/homebrew/recipe/view/569726/vern-s-munich-dunkel-ii I was shooting for about 3 1/2 gallons of kettle volume, but ended up with 5 gallons, and I dumped out some of the lower part of the runoff from my home made mash tun. I used 3.3- 3.5 gallons of water in the mash, got up to temp of 163 and added the total of 7 lbs of grains. Stirred well and left it sit for about 90 minutes. It has a very slight blue hint with the iodine, so I took out about 3 quarts or so and boiled it for about 10 minutes and added back into the mash, rising the temp doing so. Then ate supper. After supper I tried the wort and no blue at all. I opened the valve and started draining and got a LOT more on the first drain than I had with my other round cooler mash tun. This one is a new cooler, 52 quart rectangular with a depression in the center for draining the cooler. I installed a SS ball valve and about 18" of 3/4" SS screen and made it attached to the bottom on the far end with a C hook. Seemed like it drained more efficiently and thoroughly giving me more product on the first drain. Then I added hot water using my new sprinkler can, and read somewhere that you should sparge with the amount of water you wish to end up with in the fermentor. Well, the bucket got pretty full and I measured the Brix at 9.75 corrected for 70 deg. That figures out to 1.039 S.G. Now boiling to reduce the amount of water. I probably should have used a whole lot less water. Is there a way to figure efficiency with this reading, and amount of grain and final volume? Just how much water SHOULD I have used? Perhaps I should have checked the S.G. on the first drain to get an idea on where I stood with sugars in the solution.