I am currently modifying a number of my flood and drain gravel aquaponics beds into recirculating wicking beds just to see if there is any improvement in the productivity of the tubs over standard aquaponics. RWB’s are similar to normal continuous flow gravel beds allowing water to flow through the stone media at the base to assist in the conversion of ammonia into nitrites and nitrates.
The top part of the bed however is a soil layer which wicks the water up from the base. The overflow pipe is placed just below webbing material which separates the stone and soil layers. I have no idea how this will work out so I am only trying it on a few beds until I can iron out and problems and see if there really is any advantage.