Fishing in the film

[ALG]

On a recent fishing outing I was told that the fish were eating caddis emergers. I was given a couple of patterns such as x caddis, emergant cad. pupa and iris caddis. I was fishing in pretty swift water. My question is how do you tell when you have a hit. If you are supposed to fish these in the film or a few inches under, how do you know when the fish hits? You cant see it, and cant feel it, that makes it a little tough. Any advice.
thanks,
alg

[Frequent Flyer]

Alg

I've had a lot of luck this summer fishing a Trude pattern with a caddis emerger dropper across and down. They hit on the end of the swing. You see it first, feel it next. I use this more at the edge of still water, but have had luck in faster water too.