Here are
some issues I see with this design, given the image above:
1. How would you adjust the water level in the display? The tee that connects your horizontal surface skimmer really has no space below it to allow adjustments.
2. Depending on your flow rate, you might need to drill a hole on top of the tee to prevent the siphon effect that creates a sloshing noise.
3. The ends of those surface skimmers need a cap - otherwise, the slits will be useless.
4. You need a Durso-style standpipe inside your overflow box. Make that TWO standpipes for redundancy.
5. Also, why even bother using a box outside the display when you can just use a pipe directly to your sump?
6. If you're going to use an external box anyways, why not just create slits on the back of the tank and create a long, horizontal external box? Kinda like a Calfo-Style overflow
seen here Note that the picture in that thread uses an
internal box. IMO it will look way neater if you mount the box outside the display.
7. You might want to rotate the pipe so the slits are facing UP. Also, if you have tremendous surface flow, those slits may or may NOT be effective for surface skimming. (see pic below)
That thread above will give you tons of ideas for an overflow box... good luck
