for this, there is no need to do vacuum filtration.
The filters I have are not that large and even if they were it would take a week to filter with only gravity helping. Im sure you may not "need" what I have suggested. But if a two dollar bottle and a dollar pump can cut the waiting time tremendously, why not do it? Btw how long does it take to drip filter, oh say, a quart or two and how often do you change the filter due to slow downs from clotted pores in the filter?
oh, what cm is your filters? Mine are 5.5, maybe I need to get some larger ones with less retention if its that easy.