Water polishing is to remove suspended particles in the water column like sand or debris that gets stirred up. It's sort of a temporary thing like kansaslider said. If you're needing that much filter floss material to do constant polishing, something else is wrong with your setup. Clear water is NOT clean filtered water. Maintaining 0/0/low is what you're striving for. What are your ammonia, nitrite and nitrate measurements from a drop based test kit?
My guess based solely on your pictures is that you're very low on bio media. Filter floss / polyfill is great as bio media BUT it clogs and has to be replaced frequently so you're probably not fully cycled.
Our recommended media config for the FX5 / FX6 is here:
viewtopic.php?f=9&t=30145