Place the worm food in a single spot in the tub. If you place it there, they will come and eat it. No need to spread it all around. When the tub is nearly full of poop and good old compost, you can move the worms to a new tub and start over. Now you have a product to sell. As your worms reproduce, you will need to expand their living quarters also. You can drill a large hole in the side of the tub and do the same on the second tub. Connect the two tubs with a plastic tube or pipe and close off the end where the worms are. When you need to move them into their new home, just open the tube up and put food in the other, new tub. The worms will start to migrate over there. This process takes a longer time, but it is easy, less messy and less laborious. Now you are on your way to a profitable business.