Greyhoundgirl- I know you know this- but others might not.. The link I posted also shows a automatic feeder. Keep in mind- although plastic is safe for water, its not safe for food. The fat in the food will absorb into the plastic, making the plastic bowl eventually rancid. Plus- a autofeeder where they can eat as much as they want- is a good way to end up with bloat in a large breed dog because the dog can eat whenever they want- even after exercise..