I'm not the most experienced guy here, but I'll tell you what's worked for me.
If the gens are off during the day = cracklebacks or griffith's gnats ( I just got some wooly worms I'm dying to try)
If gens are running during the day = wooly buggers, cracklebacks, scuds and hoppers
If gens off at night = large streamers (dark color)
If gens on at night = I just stay at home
I use a 5 wt or 7 wt days and a 7 wt at night.
Good luck. Hope you catch a bunch.