Simon's Super Siphon

Hi, this is a flood-and-drain siphon that works reliably even on low flow rates, and well-suited for small aquaponic or hydroponic systems. 

I've been using “bell siphons” in my flood-and-drain aquaponic systems for years and have found they don't work well for low flow rates or if one would like a straight vertical drop to the reservoir. You can make much neater setups with vertical drops but a standard bell often won't fire but sits dribbling annoyingly instead. If you are able to increase the flow rate to get it firing well, you can often find it won't cut off at the low level. 

Simons Super Siphons and Turbulence Balls are much more reliable but are still cylindrical and space-efficient.

In the Super Siphon the main flow of water enters through the large lower slots, while a minor flow enters through the smaller holes on the other side. These are the entrances to a matrix of internal channels which are like inverted snorkels to extinguish the siphon quickly. Having a lot of channels allows a lot of air to enter quickly. Two levels are provided, if you prefer the higher water level cutout, use some self-amalgamating tape to cover the lower holes. The holes at the top don't do anything, these are there to allow air out of unused parts of the channels without causing the siphon to float. 

Now the Turbulence Balls. Your usual bell siphon relies upon a horizontal section of pipe. The 90 degree bends cause turbulence in the water which means the air gets expelled from the siphon. If you don't want to use horizontal pipes then you need another way to induce turbulence. A loose ball in the pipe (such as an expanded clay ball from your media) will do this if you stop it from dropping out of the pipe or getting sucked back into the siphon. I find a ball which is about two-thirds the ID works well. As the flow builds up the ball starts to oscillate and fires the siphon.

You can see in the pic how little flow can be used - and still have a reliable system.

Lastly, the media guards. These are designed to minimise lost space in grow beds but not impede siphon operation. They have a lot of holes so as to keep high flow rates for reliable cut off and the corrugations are designed to prevent clay balls clogging them up as well as form strength.

Please enjoy and let me know if these helped you! Thanks.