I know that our longtime member phat, who also is in Alberta, uses chlorine dioxide (Aquamira or Katadyn MicroPur in the US; I've forgotten the Canadian brand name) to avoid the filter clogging problem. IMHO, you still want to get some of that silt out--I wouldn't want it scouring my insides!
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May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey