Okay, so before I go crazy...I need some help from you fine experts on this board. Hopefully I'm just overlooking something simple. Here is the problem: I'm on my sixth batch of AG that has only gotten down to a FG of 1.020. I've gone way too long now without a successful homebrew and I'm just left scratching my now hairless noggin since I've pulled the rest of it out in frustration. For a few years I did extract and partial mashes and never really ran into a problem with OGs or FGs but this is killing me. I'll start with listing the technique/equipment for the problematic batches I speak of that have stayed constant: I mash in a 10 gallon pot with a mash screen using 1.3 quarts of tap H20 per lb of grain. Mash starts out around 155-7 and ends around 150-153. I batch sparge until I have 6 gallons of runoff. Full boil for 60 minutes with Whirfloc at 15 min. Chilled and into the fermentation bucket within 30-60 minutes. OGs have all been in the 1.050-55 region. Fermention has been in a temp controlled fridge at 165-170 with the FG usually being checked after 14 to 21 days. Here are any differences that I can think of: Different recipes. Grains from different suppliers (therefore different crushers). The first batch was shaken and vigorously stirred prior to pitching yeast (never a problem with all the extract and partial mashes). All other batches used pure O2 through a stone. I've used White Labs, Wyeast, Nottingham, and Safale. I've re-warmed, I've re-stirred, and I've even re-pitched a couple of times. I spoke with WYEAST and they ran me through a forced fermentation test which I've done on the last few batches and did not change the result. Same result on EVERY batch- a FG of 1.020! My hydrometer reads correctly...my thermometer reads correctly...and my fridge temp reads correctly. I've had one AG come out with appropriate numbers when I first experimented with AG but that was doing two separate mashes because I only had one 5 gallon cooler...but go figure, it came out perfect and fermented fine. Is it my water?...it tastes great and never seemed to be a problem with extract and partial mashes. Can someone please advise on something that I'm overlooking or messing up?! I just find it very strange that every batch ends up at 1.020 and nothing else...what is it about this number and why does it taunt me!? Thanks for any help!