well getting closer.... baby steps though, ugh
some of my self watering system details:
Top line is feed (and "power-off" drain) line from pump, bottom is main drain back to reservoir. Notice both lines bend over to bottom of container (This is critical).
Holes in bin are drilled slightly smaller then the tubing to self seal against them.
The top is fed using a small fountain pump controlled via timer... the pump is located in a main reservoir that is setting under the plant rack's lower shelf. The volume of water in the reservoir exceeds that required to make the system operate. The level also is less than it would take to overflow the system in case of something unforseen happening.
As the pump runs, water level in the bin increases and soon reaches the height of the main drain line where it enters the bin. At this point, a siphon forms in the drain line and draining begins.
It is important that the main drain flows faster then the feed line fills (smaller pump size is better for this reason). I have a common aquarium flow control just in case I needed to fine tune this balance, but it was not needed.
After a period of time, all the water is drained....and the hose size is small enough that the suction is maintained even as the pots slowly drip their residual water.
A larger hose size would not work as well in this application, it would "break" suction too early.
If the timer or power shuts off at a point where the water level has not yet created the siphon, the water pump's feed line then starts back flowing, forming its own siphon.
System operates normally.... cycle is completed, plants watered and drained as normal, system ready for next watering cycle.
System operates but timer stops mid cycle or unexpected power failure.... water drained via feed line, system ready for next watering cycle.
Timer is set for an hour and half.... plenty of time for at least one complete cycle.
Works better then hoped, notice the water level is empty.... the system accomplished this on its own, its been doing the watering/draining for a couple days now
Since the pots partially flood then drain, fresh air is pushed in behind the exiting water... providing good gas exchange in the root zone.
An elegantly simple and effective system if i do say so, I'm very pleased with it's performance!
Ohh and the tubs in front will be gone soon...