Pond Boss Forums GENERAL QUESTIONS Help Siphon drain

I'm not an expert (although I stayed at a Holiday Inn Express last night) but it almost sounds like your system is sucking air through the outlet rather than water through the inlet? I can't picture how this system would have been built to have that as a possibility, but blocking the outlet causing the system to start certainly points that way? Basic Fluid Dynamics principles would indicate that air draws easier than water - but again I don't get where in the system this would come into play, on a standard siphon. A leak higher in the system maybe, but simply the outlet hole? I don't get it.

Do you have a schematic of how the system was built?

More knowledgeable folks than I will certainly chime in soon....