How do I quickly change the weight of my Man Bag?

Like everything else you own, your wife wants to share you Man Bag too.  But, how do you easily change the weight in the bag from 80 or 50 lbs. for you to 30 lbs. for your wife?  We came up with a groovy way to make the transition simple: 

Step 1 - Mark a 5 gallon bucket:
    5 3/4” from bottom ≈ 30 lbs.
    9” from bottom ≈ 50 lbs.

Step 2 - Fill your Man Bag™ to 80 lbs.

Step 3 - If you want your bag to be reduced to 30 lbs., then empty sand from your bag into the bucket until it reaches the 50 lbs. mark.  Empty or re-fill your bag in increments of 30 or 50 lbs. to easily transition between 30, 50, and 80 lbs.