Awesome nano, and bold for the number of "large" gig carpets, but still curious about your flow and light regimen, plus you "promised"...
I can only take new pics once I am back home, as I am currently out of town until the weekend.
Flow is currently provided by a Maxspect gyre 130, but I am adding a second one attempting to recreate an even more natural flow motion.
After spending a lot of time observing my gigs, I realized that according to different flow patterns they open up more or less.
Also, depending on the flow pattern, their oral disc ondulates forming the typical gigantea wavy shape.
Specifically, in my tank, the neon green is the 'happiest', because it happens to be in the sweet spot, getting just enough flow without getting pushed around. This is the reason (besides redundancy) why I am adding a second gye placed on the opposite wall, so I can recreate a gentler, but steady and slow undulating motion.
As far as lighting goes, I know from personal experience living in Asia many years, that gigs thrive in shallow waters and in many cases are exposed to low tides and intense lighting. During low tides I even saw birds pecking at gigs looking for small crustaceans hidden under the rocks.
My lighting setup is specifically targeted for gigs.
I use 3 Kessil lights, a 360N, a 160 tuna blue and a 160 tuna sun. The 360 and 160 tuna blue are connected to one channel of the kessil controller, and the 160 tuna sun and connected to the second channel.
That way I can blend the color spectrum as well as the ramp up and down time with finer control. I try to mimic as closely as possible a more natural color spectrum. That's where the 160 tuna sun comes into play. I ramp up and down the color temperature from 6500 to 9000K and back to 6500.
At noon I have the highest intensity, with all lights at full 100% and coincidentally, that is the time when all the gigs are open the fullest. Then I begin slowly ramping down from 4pm to OFF at 8.45pm, then back on at 6am.