I tie fur ants with dry fly hackle to float them, but they still sometimes float even with soft webby hen hackle. When I tie ants for below the surface, I tie the body segments with thread, coat them with Sally Hansens, and tie in soft webby hackle to the midsection as Jay said. The thread ants drift down below the surface, which is the ticket sometimes, especially in low clear water. Tie the wet ant as a dropper off a dry fly and you have a great summertime tandem. Tie your ant in as small a size as you think the fish can see, and than subtract 50% from that.