Bell siphon construction - part 2

These are the drawings on what sized pipes I used in my system.  Consider the down tube arrangement a good starting point for your system.  It will have to be tuned and that will be covered in part 4.

Lets start with the stand pipe(right) first.  The 4 3/4" is the depth of the water in the grow bed.  You want it to be 1-1 1/2" below the top of your growing media.  For the Sterilite container I used this is the max water depth I can have due to holes left by the locking lid.  The stand pipe is made from 1/2" pvc pipe with a coupler on top and a grey(electrical) pvc slip to threaded adapter.  For the bell a 1 1/4" pvc pipe and cap is used.  According to just about every resource on the web the bottom of the pvc cap on the bell should be at the same height as your stand pipe.   In the top of the cap a hole is drilled the same size as the air tubing.  You run this air tubing down to the top of the slits at the bottom.  I cut it at a slight taper.  This is to break vacuum and stop the siphon once the water is down to the lowest level.  The slits at the bottom are of course to let water into the bell.  They should be at least 3/8" - 1/2" wide and there should be 4 of them.


Here is the drain pipe it also from 1/2" pvc pipe.  Make it close to this.  Part 4 will explain how to adjust it.