This is my first Instructable.
I'm new in the aquaponics world, and my first aquaponics system was a failure due to rapidly and fast changes of water in my grow bed that cause movement in the clay-pebbles. The system was build with a U sifon that i actually still prefers but i think it more suitable in larger systems. So i build myself a classic bell sifon with a small twist.

Step 1: Standpipe

First of all i got hold of a standpipe that was larger in the top than in the bottom and as a bonus it had a extra tightening in the bottom.
I measured the requested depth in my grow bed and cut the stand pipe 30mm below the clay-pebbles.

Step 2: Siphonpipe

Then i mounted the standpipe in the grow bed to measure the length of the siphon pipe, i added 5mm above the standpipe. + cut out some teeth in the bottom to let the water flow in to the siphon pipe.
right above the teeth i drilled a small 5mm hole in the standpipe that helps the siphon to stop by sucking in air when the water level is below the hole.

Step 3: Mounting

Then i mounted and started the system and it drains the system great after regulating the water inlet.
The time between the drains are now just above ten minutes, and before with my U sifon it was around 4/5 minutes