The process has evolved a good bit since the beginning. Most folks do not use the double buckets and just mix their mix thick enough that it doesn't need straining before serving. You won't want to refresh the feed and water each day, as you will want the feed to have time to get fully fermented and converted, so it's best if you just mix a bucket and when it gets low but not empty, fill it back up with feed and water so the old mix can jump start your new feed and you can start feeding it out the next day.
Say, halfway or 3/4 down?