On my sonar in CB they usually are a line 1 to 3 feet thick on or just off the bottom across the whole screen. (Good ole days at least)

In WB I see them that way sometimes but more often small arches stacked on top of one another. If there are enough of them, its a line across whole screen. The arches tell you the size of the fish. If you don't see a few arches, they could be only 5 or 6 inch fish.

Rickerd