For faster or deeper water, use a big fly tied on a size 8 to 12 hook, and weight it heavily with tungsten bead heads and/ or nontoxic wire. For slower or shallower water, use a small fly tied on a size 12 to 16 hook and weighted only with a bead head or only with wire.
( Yvon Chouinard )
[ Simple Fly Fishing: Techniques ]
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