how to calculate water flow

[sebastiaan153]

so im in the middle of designing a reeftank and im wondering how to calculate the amout of water that is able to flow trough the gaps. its a tank of about 200 liters and want 40x flow so about 8000l per hour. how do i know these gaps are big enough.

 

[KStatefan]

This will estimate the flow thru a toothed weir

http://irrigation.wsu.edu/Content/Calculators/Water-Measurements/Rectangular-Contracted-Weir.php
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