One thing my FF is doing lately is after about a week it's smelling so off that i'm throwing it out and the birds won't eat it either. i use Scratch n Peck crumble and a pellet mixed, stir it daily, blah blah etc. It smells sour good until it starts smelling like dog vomit and i have to throw it out and the hens won't eat it anyway
So i guess that i'll just have to make a new batch every week. shrug.
I had the same problem with mine in a 5 gallon bucket that was usually 3/4 full. It would get so bad that the chickens just wouldn't eat it and I'd toss it into my BSF bin for the grubs to eat. Eventually I just quit making it since I was tossing a lot of feed. What I started doing a few weeks ago is making a much smaller batch in an empty protein powder container. I'll feed about half of the batch in the morning, top it off with fresh feed and water, put it in a spot that gets some good sun during the day (the container is black and heats up nicely) and then it's ready for the feeding the next morning. Our birds are once again inhaling the FF before they head out to free range for the day. I feed them regular feed in the evenings.
RichnSteph