Buzzard11 3/4 of a pan with water added to the sawdust provides a nice heavy smoke for around 3 hours or so. You can replace maybe once during a long pork but smoke.
Walton’s sells large bags (40 lb) of sawdust for pretty cheap. My wife made me some sealed trashcans containers for both Hickory and Apple. But then again, I smoke a lot.
There are some people here who don’t like to add water to sawdust - I do, it works for me.
BTW - You should watch Jonathan’s PK100 review on you tube to see how much water he adds to sawdust.