I tried experimenting with something last year. I work Frog's Fanny
(i.e., hydrophobic Cabosil) into the dubbing of my dropper nymph
(preferably done when I tie them, but it also works after the fact).
This makes the fly buoyant and causes it (I believe) to float above the
weight or above the weighted top nymph. The fish seem to like it, and it
results in fewer snags. Some say that the Frog's Fanny makes bubbles
that imitate a natural.

BTW, I prefer using weight instead of bead-head nymphs.

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