Getting 4 doesn't mean getting a pair.
I have always stuck with my rule of getting 6-8 for a pair. Never failed me yet.
As for info about them, it's pretty much standard Sub-tropical Channa care.
Aim for 18c for most of the year, a little warmer maybe for summer months.
Very aggressive (IME) even toward their own.
Densely planted tank, plenty of hideouts.
Lots of floating plants are great, dim lights, low current.
As with all my Channa I add Kettapang leaves to the tank.
IMO, tank size for a pair should be no less than 90cm x 60cm x 60cm