Most people use this method https://tikktok.wordpress.com/2014/04/13/fermented-feed-faq/
They started out with a soupy FF that needed to be drained and found the dryer FF was producing the same results with the poultry with less work.
I definitely find this method to be the easiest. Just one bucket. Are usually keep the same bucket going for a few months. Then I completely clean it out and start over. Occasionally I'll put a little butter milk in there, or maybe a little apple cider vinegar but otherwise just feed and water.