For sure, I don't think there is anything wrong at all with the capacity at this point and it's ability to work with a 4" column. I'm speaking specifically of just using 5 gallon washes inside. Heated from the bottom, sure no problem but I don't have a can in front of me and thus don't know if 5 gallons of wash will sufficiently cover the element or should I just count on 10 gallons. The reason I'm asking and trying to deduce rigidly in multiples of 5 is because frankly I've got quiet a few 5 gallons buckets. I realize there are other size options out there.