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First and foremost, thank you for the kind words toward my work!
Top is gatf, middle is cf "big eye", bottom is probably vatf but could possibly be cf. big eye or cf. fat vatf. Even I have trouble telling them apart in pics at this size, but in person its not really a problem.
In my experience lighting doesn't really seem to matter so long as they're not kept in total darkness. I'd leave my fish sometimes for a couple days in a row under the moonlights with no more of a day/night cycle than what light comes through the window. It never seemed to affect their feeding. The fish didn't seem to care.
I actively ran experiments with water conditioning. At the time, I lived in Missouri which had horribly bad liquid rock, so my water was always really high in gh and kh. Using peat filtration, I was able to dial in my ph from the almost 9 of the Missouri aquifer water to 5 and the color of sweet tea with the peat. The fish didn't seem to care.
The current misconception, which arose through a poor choice in wording on my part about seven years ago, is the greatest failing I've made in this hobby. They do NOT need current, but they're not stressed by it when done correctly, either. When they have current, they need a dead spot and smooth flow. As to how much, so long as it isn't obviously stressing the fish, you're good. The main advantage of current is that it gives them a treadmill of sorts which allows them to burn energy without smashing a tank wall. IME, it allows them to thrive in a smaller tank than that which a large, dynamic predator such as them would otherwise need. It isn't a critical requirement.
The most important part of keeping ATF is a low stress environment with lots of do2 and a concerted effort to keep no3 below 20ppm. Low do2 or high no3 WILL stress the fish to the point of not eating and shedding slime coats very quickly.