internal overflow & durso pipe?

[allen1973]

Pretty soon I'll be making my internal overflow.I've seen them with grooves cut on the side toward top,I've seen them teeth on top,and heard of no teeth on top.Which is the best one to do?Also I seen directions on making durso standpipes and seen them in lfs,can someone explain the mechanics of them?I've seen holes drilled on sides,on tops.do they siphon like hob overflows? :help:

 

[cgrant]

I have the all glass built in overflows, they have the teeth on top, very quiet, especially for the amount of water I am moving, 2400gph pump/210 tank.

 

[shiby1510]

make some sort of template and then cut teeth into the overflow... As for a durso it is used because sometimes there is a suction noise or different kinds of noises that are from the water flowing down to your sump a durso pipe can elimnate this sound because the sound is from not all of the water flowing down evenly and creating an air gap which makes this sound... a durso eliminates this.. a durso will take you about 5 mins to make they're very easy... but not necessary for an overflow it is just something if you want to make if you find that your overflow is being noisy.. but like i said its a case by case thing so peoples are ... some aren't.

 

[acrylic51]

The teeth are to keep unwanted things from making their way into the overflow box.......Either way will work. You can get a dovetail jig and use that to route your teeth, you'll just have to decide on the spacing of your overflow teeth and possibly have to get a different size template for the dovetail jig, as well as the bushing for the router and bit, but works very well........
The durso's work very well. I haven't used them with the holes drilled in like alot of people do....What I did was drill the top cap and tapped it to accept a threaded air valve and that way I just adjust the air valve to get things where I need them to be.....HTH