I have been asking the same question lately. I have heard alot about Pink Pollywog. Also Battle Creek Special and Polar Shrimp in size 2. You may want to do a search on the forum for silver salmon. I have seen some other post not too long ago about silvers.
I like to use a floating line with a weighted fly or a spil shot ahead of the fly. My buddy likes the sinking tip with a shorted leader. I think it is personal preference. I think it is easier to mend with the floating line. My favorite is a large purple fly with a bunny strip tail that swims as you strip in line. It has proved to work very well on the gulf coast.
My #1 all time go to Silver Fly is a Starlight Leech. Comes in multiple colors and is very heavy. No need to use sinking line with this fly, if you need to get down deeper, use some lead line between your leader and your tippet.
I would have to go with Red or Black as my favorite color on these.
Pink Polywog is good but sometimes the Silvers don't want to come to the surface.
Just a thought. I love chasing Silvers from PWS, Kenai, Parks and Delta. I have found over the years believe it or not a standard Cone Head or Bead Head Woolly Bugger in various size and colors produces well. That being said ESL or Electric Leeches or articluating leeches fall in that same catagory. I know it sounds like a far reaching solution to fishing Silvers in all cases however they have been extremly dependable for me. I also fish a standard WWF line and add shot when required to fish the proper depth.