take the 25 then place the 73 inside that, then the 160 inside those then the 220 inside of those, the 220 should be the bag that catches all the contaminents such as leaf matter, which you dont want in your bubble hash, the smaller the size the tighter the screen will be. the 220 allows the trics to pass through but catches all the leaf matter. you will catch all of the trics in the lower sized bags. i will take a guess and say you will have your best results in the 73 bag. hope this helps bro