I was more or less just adding it to keep it going for sure while I was gone for several hours. I probably had maybe 5lbs of charcoal In there at first and felt like it had burnt a lot more of it then I expected when I checked on it. I'll can't remember what the bottom grate on my basket is but I think it's like 18.5" maybe. This was my first time using it and first time smoking on a charcoal fueled smoker so there is some learning to be had with the fueling of the fire.