Vaccum purge time ? And clolor

Hey there folks..
Looking to get some insight on my closed loop system .. I got recently passed friend . I know how to run it and everything ..
I am just confused on some of the tubes on one of them is filled with nothing but these little brown balls fill to the top ?
I have celite 545 what is this for ? And bentonite clay ? How doing use these .. do they produce better color

The Celite and bentonite clays are typically used to remove polar elements, which typically are colored.

10.7.3 CRC 101, Intro to CRC and packing a poor man’s CRC - GrayWolf's Lair (graywolfslair.com)