What coloration pattern helps camouflage catfish by contrasting their top and bottom sides?

Answer

Light ventral sides and darker dorsal sides (Countershading)

The countershading pattern provides camouflage by making the fish blend with the dark bottom when viewed from above and the lighter overhead light when viewed from below.

What coloration pattern helps camouflage catfish by contrasting their top and bottom sides?
appearancefishbodyCatfish