Stephen Crowhurst
Senior Member
You mean ectothermic right?
Technically most fish are neither truly one or the other. Some are actually more endo than ecto and vice versa. In simple terms fish are cold blooded with some ability to raise their body temp a few degree above thier surrounding, the ability to do this varies between species.
Barbel belong to the family Cypriniforms (Carp like fishes) which to my knowledge are not particularly skilled in self heating.