Create a loop, then test it

A lengthwise return and intake near the downstream zone often form a useful loop, unless wood and rock divide it.

A low intake can receive solids but must avoid substrate and livestock. Surface film requires upward momentum or overflow capture.

Use observation as a tracer

Watch harmless food dust and record settlement. Change one height, angle or side at a time.

Do not make fish fight a narrow jet to compensate for poor distribution.