Internal Overflow

[Chago09]

I am just curious.... why is it that the teeth are made in the top of the internal overflow???? why not just make it a flat edge about 1/2" below the water line and let it overflow just like that??

[rob28]

More than likely it keeps most fish out of your fuge...IMO.And unwanted debris that may clog your drain?

[xian]

Thats it

[eckrynock]

<a href=showthread.php?s=&postid=10263556#post10263556 target=_blank>Originally posted</a> by Chago09
why not just make it a flat edge

That's actually the best way to do it. If you're making your own, don't add teeth.

[Chago09]

seriously??? I have not really seen a lot of people doing that

[eckrynock]

Look at some of the designs in this thread. http://www.reefcentral.com/forums/showthread.php?s=&threadid=473152 Teeth collect debris and proteins, though minimal, you still lose efficiency. You can see my internal overflow in this pic:
http://i60.photobucket.com/albums/h24/eckrynock/skimmer002-1.jpg

[dwd5813]

thats a pretty sweet lookin return system you got rockin there

[iflipsidei]

Some people cut their teeth and add a plastic mesh to get the maximum flow while still keeping those gobies and snails out of sump playground

[iamwhatiam52]

This is what I use to keep my tiny gobies and shrimp out of ny sump.http://reefcentral.com/gallery/data/500/125081Overflow-screen-med.jpg

[wooden_reefer]

There is a better reason.

It is to make the rate of overflow match the rate of return, more or less.

When the rate of return increases, the water level of the tank tends to increase. The increase in water level also increases the crosssectional area of flow at the overflow. Thus limiting the rise of the water level.

So the length (height) of the teeth, usually about 1 to 2", has a purpose. It tends to make the rate of drain and the rate of return match, but there is a limited certainly. The teeth cannot be way too wide for this to be effective.

Of cource, it also breaks open and skims the surface, but an even level overflow would do that too.