Micro Stone (Size 18)

The Micro Stone imitates a tiny stonefly nymph or small dark aquatic nymph drifting near the bottom. Stonefly nymphs usually crawl along rocks and structure, and many species spend a long time underwater, making them available to trout well beyond the actual hatch window.

Fish a size 18 Micro Stone when trout are feeding small but you still want the buggy profile of a stonefly-style nymph. It is especially useful in clear water, pressured streams, winter or early-season conditions, and smaller freestone creeks where tiny black or brown stoneflies can be part of the menu.

Fish it near the bottom under an indicator, in a Euro-style nymph rig, or as a small dropper behind a heavier fly. Trout often hold low where current is slower and food comes by with less effort, so a small nymph needs to drift naturally in that lower feeding lane.

Use a size 18 Micro Stone when trout are inspecting larger nymphs but refusing to eat. It gives them a smaller, cleaner version of a high-protein bottom bug without the “too much cheeseburger” problem. Small flies can be deadly when the water is clear, the fish are picky, or the naturals are simply tiny.

Fish it in riffles, pocket water, shallow runs, seams, and rocky stream sections where small stonefly nymphs can get dislodged. Stoneflies are closely tied to clean, cold, oxygen-rich water, especially around rocks and current, so this fly belongs anywhere little bottom-crawlers might get knocked loose and sent drifting past a trout’s nose.