Internal Overflow Box Placement

I will soon be installing my internal overflow box but am not sure how far down to place it so that the waterline won't be seen. I have the BRS 1200GPH overflow box (Aquarium Overflow 1200 GPH Overflow Box - Bulk Reef Supply).

I was thinking to install it so the bottom of the teeth openings are level with the bottom of the trim on the tank. I think I read somewhere that the water level will usually be 1/4" above the bottom of the teeth openings? What do you guys think?

 

You can do the top of the teeth basically right up against the rim of the tank (well maybe 1/4" or 1/2" lower). That should work out fine I believe.

 

I think you can also adjust it once it's all up an running to get it where you want.

 

+1 that's what I would do. Right up against the trim ring on top or slightly below it.

 

Thanks guys. The only thing is I'm planning on doing a Herbie drain and need to fit two 1" drains in there (emergency & main). If i put the overflow almost flush to the top, one of the bulkheads is set a little higher so the higher bulkhead nut will interfere with the trim. I did a mock up to see how close the holes can be, but will do another to bring the higher one lower to see if it will clear the trim but still be able to clear the other bulkhead fitting.

 

Oh, now I see you are actually mounting the box to the glass.
Acrylic to glass? HHhmmmm.

I'm also going with a Hergie, the ID's 1&1/2 in. on my 180.
Cept I'm doing a Coast to Coast with glass.

I planned on putting the top of the overflow at the bottom of the trim line.
I don't have slots though, and will probably go with gutter guard or egg crate as the grate.
Here's my bottom and front glass: