Funny video on HuffPost, showing two worm bins side by side and giving a little critique of the differences.
I gleaned some good advice -- looks like I'm putting too much food in. You shouldn't put food in the next highest level until it's all eaten in the current working level, but I've got food to spare and it's in the higher levels. What this means is that the food will sit around longer and get a little grosser before the worms are ready to come up and eat it.
What this also means is that I either need more worms... or another bin. Who's going to tell Pete?