The boys and I first did this experiment back in July and we really didn't feel that it worked well.
We discussed what we thought went wrong and decided that perhaps the type of paper towel played a significant roll.
In our first experiment we used a very inexpensive generic brand of paper towel that was thin and rough and we thought, perhaps not very absorbent.
So we purchased some premium branded paper towel, tried again, and happily saw a much different result.
Our first experiment took 18 hours from start to finish - this one was MUCH quicker.