When in doubt, go big. Especially when dredging at night, in muddy water, or well under the surface with the fastest sink-rate fly lines. In clear water, using larger flies is not so critical. I sometimes go to dark patterns — brown, purple, black or combinations thereof —in muddy water during the day. When dredging for snook at night, however, I mostly stick with the same white flies I fish closer to the surface. As far as hooks, I know fly anglers who have gone to circle hooks for this kind of fishing, claiming the hookup ratio is better and they make catch-and-release easier. But I still use J hooks, primarily because dredging is fishing by feel, and I habitually strip-strike sharply when I feel a grab. Nevertheless, I find that many fish hook themselves on a J hook anyway, against a taut fly line.