Left and right sided streams

[Nain]

I have seen several references in Linke & Staecks dwarf cichlid book to left or right sided streams. What does this mean?

[Mike Wise]

When you look downstream (the direction the water is flowing toward), right bank streams enter the river from your right; left side tributaries enter from the left.

Examples:

The Amazon flows from the west to east. Therefore, the Rio Negro is a left bank tributary & the Rio Madeira is a right bank tributary.

The Rio Negro flows northwest to southeast. Therefore the Rio Branco is a left bank tributary & the Rio Uaupés is a right bank tributary.