Brandon,
In my experience, if you don't replace the filter sock every couple of days, it would be better to just run your tank without one. Also in my experience, you'll need to replace them that often anyway because water will stop flowing through them as they gunk-ify (this could be a result of my filter sock being low in the water so there isn't a ton of pressure from gravity pushing water through the sock).
What I'll usually do is run one for a day or two after a water change (during which I blow out my rocks with a powerhead). This gets a lot of the junk out of the water without having to worry about the nitrate trap aspect.