Haha cool, was jsut reading up on exactly those. So let's see what I found otherwise:
Some say they top out at 15cm (6"), some say 25cm (10") at max for the males, nobody said 9 cm though. The 'blue' variant from Assam might stay a bit smaller though from what I read. It is a bit hard to tell males and females apart but females tend to stay smaller and will appear rounder when ready to breed.
They like well planted tanks or at least should have many hiding spots. Some seem to prefer keeping them in soft water but they don't seem to be too picky, however when breeding soft water seems better, else the eggs tend to fungus.
Since they can breathe athmospheric air and tend to jump out of the tank, it should be well covered.
They form pairs which generally get along well but there might be some agression at times still. With others of the same species or other snakeheads, they can get very agressive and should therefore be kept as pair or at least in a big tank (not that us cichlid keepers wouldn't be used to that, lol).
Channa bleheri is not a mouthbrooder like other small species but builds bubble nests. Like I understood it, they then transfer the eggs to some spot on the substrate, and the male will guard them.
About feeding, it seems like what predatory cichlids eat should be good for them as well, like insects, earthworms, bit of fish etc.
It was about the rainbow snakeheads when I read they should have cooler temp in winter because it is like that where they come from. They are said to show better colours then, breeding is easier and they are less likely to get sick. Otherwise the normal tropical temp like 25C.
Can't think of more for now, it is anyway what was said in various articles, so no real idea what of that is really true and important lol.
