I've caught trout on these down at least 10 feet below the surface. I don't know if "drowned" ants ever really get that deep, but I guess trout are "programmed" to eat a well presented ant anytime or place they find one.
On FlyFlasher.com you can find 39,690 flies from all over the world. Flash your own fly patterns, upload your current work or search for inspiration. The flies are tagged, so you easily can search for them.