As I've said multiple times in class:
Sometimes 1/6 herbs are allowed to be used in at 1/18 - if they are strong and highly aromatic
Are 1/6 herbs always allowed to be used in the 1/9 connector area? yes
Can herbs only go down in dosage once? yes
1/6 ok to use as 1/9? yes
1/9 ok to use as 1/18? yes
What if something says 1/72, can it be used as a 1/18? No, nothing goes up, right now you cannot use anything less than 1/18 part, so no 1/36 part. no 1/72 part, no 1/144 part herbs