I recently brewed two batches of an english bitter. Both were AG.One was brewed using my gas stove, the other was brewed using a newly puchased fryer. Both went well. They were conditioned in kegs and then cooled. I tapped the stove top one and everything was great. Nice clear color nice head. The other one looks like mud. I even poured two pitchers worth to see if maybe it was some type of sediment. The only difference was the fryer.
Did I let the wort get to hot with the fryer. It's my only thought.
If you drink. don't drive. Hell, don't even putt!