This second post on same topic to include diagram.
Not exactly Bell Less but made this siphon without its normal 80 mm bell. Its getting difficult to source the 80 mm end cap so I decided to try using the outer strainer as the bell itself.
Diagram below illustrate this siphon.
Nothing special just that the inner bell is removed and the vent cowl is replace with an end cap. This will make the siphon cheaper by a few ringgit and less components to worry about.
This siphon need to be tested against root growth.
Strainer bell can be of smaller diameter but this size was chosen on all my siphon due to ease of cleaning, that is the only reason.
Completed Strainer Bell Siphon above, that holes on the bottom needs to be of smaller size, this is using 10 mm drill. The bottom end cap will need to be drilled too making water drainage better.
As previous post, water cut off occur at top rows of drilled holes, in this set up there is about 1.5 inches of water left upon cut out.
Newer sample above with single row of drain holes, this from my latest growbed : Here that I'm testing that will drain really low.