arduino's have a future in aquaponics in my mind.  Not many people talking about their use of arduino's and aquaponics.  Windowfarm groups are much more active with arduino's and control of systems.  I have just completed my auto mode function that I presented at Make:SF meeting featuring aquaponics in the Bay Area.  The auto mode function controls the following components:

water pump - controlled by relay with timer function for turning on and off when needed

media probe - determines water level in grow bed will cause water pump to shut off when needed

gravity feed valve -  drains grow bed after time period

float switch - controls water level in tank and protects water pump in case water gets to low in tank

start button - when pushed starts auto mode function LED lights goes from red to green for on

My media probe needs to be re-calibrated and I am moving to a new resistor configuration on this demo unit.  Once completed I will do a video to demonstrate the functionality and how the cycle performs.  I will next develop the KILL BUTTON function.  Then move on to 4 one-wire temperature probes and LCD display of options and temperature readings at request of user.