silica wick seems to be the standard, its in all the clearos, atomizers, cartomizers etc
only exception I'm aware of is the rebuildable atomizers that use stainless steel mesh rolled up into a wick
health concerns aside, the conclusion I've drawn is that silica is great in that its burn resistant, but is a terrible wick. Cotton and stainless steel kick the crap out of it so bad its not even funny. Its just a bit of a learning curve to get things dialed in right.
I've been vaping two stardusts side by side since a few days ago, one silica, one cotton, and the cotton one is shaming the silica. no dry hits, fast wicking, clouds of vapor, cleaner flavor. and when you do get the 1/100 dry hit at the bottom of the tank, its not as gross as with silica.
So silica is the stuff that is normally around the heating element in cartos? I do not see that around the element in my DCs. They look to be just exposed to the cotton from what I am able to see without opening it up.
I do remember seeing that around the element in the older cartos.
Still, I would have to think that the cotton filler filter those fragments.