Hi, in my nzxt phantom full tower case a lot of fans and a lot of room for more fans.In every fan "hole" theres a black thing that is as wide as the "hole", i would think its a dust filter. Without knowing this though i took them off a week ago, and recently i thought of the possibility of them being case filters. I took them off because i wanted my LED lights to shine brighter through them since they were letting very little light out. Is there a problem to running a pc without filters? if it is, do i need all of them? or only where i got an intake fan? ur thoughts please guys...