We ran into the same problem in July when we fished Indian lake (about an hr. East of forth lake, but similar fishing). Marked a ton of bait but did not move a rod in two days. Seems like it was a great year in the adirondacks for smelt.
Do you happen to have any slide divers with you? In previous years they have always produced well for me on the ADK’s. 50-70 foot leads of the diver with small spoons or smelt imitating plugs (2 1/2 to 3 1/2 inch spoons and sticks). Best colors for us have been chartreuse/green, blue, and copper for the Lakers, and orange for the landlocks. Best luck on landlocks has been from 35 to 55 ft down and faster speeds.
Another thing that has worked well for me up there is fixed cheaters 10 ft above your mainline. For some reason the cheater seems to take the majority of the hits compared to the mainline lure.