PlanetCatfish.com

on the first of January I visited a friend to get some Hoplosternum punctatus, but I was most surprised by his Doras punctatus. They were very active swimming in his tank

I have myself a group of catfishes named as Opsodoras stubeli - which I hardly ever see. They are healthy, but als long als the lamps are on, they remain in darker areas.

Doras punctatus is a species with light colored body, Opsodoras stubeli is dark, almost black.

Now I wonder - do the others with this species have the same experience and can one say body color in Dorads tells how night active the fish is?

I don't have any experience with dorads, but I bet that there is a correlation. If a fish goes out at night, it is better camouflaged if it is darkly colored as opposed to light coloring. On the other hand if a fish goes out in the daytime, a dark body would contrast with lighter surroundings, making them easier to see, so a light body would be better for those fish.