Their setup, make use of gravel grow bed Siphon Flood & Drain and Deep Water Culture using polystyrene foam raft as growing floats. These are housed in a Polythene "Green House" to protect from bugs and the elements.
DWC and the Flood and Drain sets are isolated in their water source, with a big swimming pool tank for the DWC water reservoir and fish tank, feeding DWC channels via filtration.
Fish tank stock with Tilapia, Green Kelah and few other fish.
Leafy greens, beans and Okra grown in this DWC, with salad and kangkong below
Flood and Drain in the opposite side on the other hand utilizing growbed over the fish tank approach. This is the simplest way to do Aquaponics.
Rows of growbed over fish tank which about 2.5 feet across and about 50 or 60 ft long but its quite shallow around less than 1 ft deep stock with few Tilapia and gold fish.
Cucumber, Tomatoes, Beans, Chili and Okra are grown on the flood and drain side.
Okra looks a bit thin. Edwin pointed out that these Okra get infested with aphids it stunt their growth.
These Tomatoes according to Argustine is about 4 months old.
They are having problem with high acidity, PH dropping down, contrary to what I would expect as Limestone gravel used as grow bed it should swing the PH on the opposite side of the scale toward Alkali.
Its also affect the DWC system more than the Flood & Drain. From my short observation, I can't see any thing differ in their Flood and Drain setting to others, also the DWC is of standard installation.
Plants are not doing well, one reason I could see is that some plant affected by growbed not fully matured this causes stunted growth, that don't recover after growbed reaches maturity.
I'm a bit concerned about the polythene "Green House" it cause the temperature inside to shoot up very high. Its okay for temperate country by over here its can be a killer.
I would suggest green house material are made from those mesh type of nettings that keep away insects but do provide free air flow to not heat up the space underneath.
In all they are starting out, and lots of things to learn. I'm sure they'll get it sorted out as they progress.