BK-I was assuming that the sparge was where at least a few points were. Would one just recirculate/sparge for a longer period of time? Say 45mins-hour? I currently average 72-80% in a plain ole cooler system, but am very interested in what you and jkarp have done with these two vessel systems. I'd like to reach a 75% average efficiency, I was just curious if it were the equipment that was limiting or your process. We each have our own process, and if the beer tastes good all the better! I'll be starting my own build thread soon, but I assure you, it won't look nearly as nice. Cheers to you sir.