when it gets colder out i usually hang a fly under a strike indicator (haven't tried this on stockers but it worked on native lake dwelling cutties) , i just make casts in areas i think the fish will be holding up and cast,then let it sit for a minute,maybe a bit less. if i get no bites i slowly strip the fly back, make afew pauses and then cast in a different spot. casting at the edge of weedbeds has been the most effective. this worked in green colored water in 32 degree weather. I figured since the fish were slugish they would like something that isn't moving because they dont like using their energy up when it gets cold out. ive caught fish on this rig in all kinds of weather, it's a great way to search for fish, often works when nothing else is (trolling,casting and stripping flies etc) the flies i was using for this rig are kaufmann mini leeches,sizes 12-14 i believe the movement is kinda key,especially in a choppy area where the waves give the fly lots of movement while it is still in place. ive fly fished a few stocked areas this year and found the same thing to happen, we had a banner day catching a ton of fish between the 3 of us then another day it's skunk city