I was reading a thread on using sand or a brick, covered in aluminum fol instead of water. I use a CharGriller barrel offset smoker and have had issues [see posts elsewhere] about temperature control. If I understand this correctly, the brick or sand help to keep the inside of the unit temperature. Which works best? How many bricks do you use? My unit is about 760 sq. inches plus offset. Do you use water as well? I know, lots of questions!