Hello Rob I'm sorry to listen to about that Terrible experience you suffered. Relating to your question, gravity feeders are functional simply because you don’t have to have batteries or complex methods for them to work, having said that most gravity feeders need slightly shaking once in a while for https://bestcatfood89998.blogsvila.com/37990641/the-smart-trick-of-cat-food-ziwipeak-that-nobody-is-discussing