If you have ever had a fish tank, you have owned an operating siphon. A siphon is a handy device for emptying out a liquid reservoir that has no drain. As a result, they are great for cleaning fish tanks. Liquid in a siphon flows "uphill" for a portion of its journey through the tube. In this project, you will determine if there is a maximum height for that uphill part of the siphon, before it ceases to function.