Hi,
    How do you know how porous a particular type of paper is? I suppose
filling it with water and timing how long it takes to drain might work if
they all were the size of coffee filters, but the smaller sized ones (tea
bags) would be hard to measure. The porosity is obviously important to allow
proper infiltration. So, any old piece of paper won't do. So how would one
choose one over another.
Amos Brooks