Staging Silvers

So I have a little spot that I fish each year around this time and every year it is the same thing - some times I catch them and some times I don't. It's amazing to me that I don't catch a lot of fish when I am surrounded by several hundred fish. I think my best day ever was about 12 or 13.

Yesterday I caught 3, today there were twice as many fish and I did not touch one. I went thru almost every fly in my box tonight trying to get them to bite.

Any advice on techniques or flies to try and get them to bite?

Here is a short clip of the fish swimming by:

I hooked a fish this morning that I'm pretty sure was a small silver, and definitely of the staging variety. He took a size 6 soft hackle type fly I tie for chums. Pretty sparse.

I think when they get to that point just being there when that switch goes off that makes a few fish turn into biters is probably just as important as the magic fly.
BTW... you didn't happen to go into the fly shop in Poulsbo yesterday did you? Your picture looks like a guy I saw at the shop yesterday asking Bill similar questions.
We are fishing for staging coho on Van Isle as we speak. Very small sparse flies. Vary your retrieve. I have been using size 8's very sparsly dressed. I know some of the guys are going as small as 14's. Neils in varying colours.