Teeth or no teeth?

[jc03]

I'm going to build my own coast to coast overflow. Are teeth necessary? Thanks.

 

[RocketEngineer]

Actually, teeth were someone's idea gone bad. They are actually detrimental to the functioning of the overflow by reducing the surface skimming capability. Plus they fail at keeping fish and snails out of the overflow box.

 

[DavidinGA]

They're actually very good at keeping fish out if you have the top of the box covered. You'd need some tiny little fish to squeeze through most overflow boxes teeth...

 

[RocketEngineer]

And if the teeth are small enough to keep said fish out of the overflow then the surface skimming of the box is significantly impaired. A better solution is a straight edge overflow with a lid that sits just above the water surface when it is running.

 

[Aquatron]

I agree with both above with 1/4" would be the widest between teeth I have gone. But installing a lid just above water line per RE makes that a nice option also

 

[SGT_York]

A dark lid works the best it keeps the algae growth down lowering maintenance and reducing the risk for clogs.