Internal overflow question

[TripleT]

Good questions, especially the one about wave makers.

Being a noob here I would hope that some one will correct me if I am wrong!
The overflow is siliconed to the glass. Attaching to the plastic trim is just asking for a future leak to happen. External overflows usually collect from drilled holes or a cutout. Internal overflows are sized and siliconed to the interior of tank.

Herbie setup is what I have planned for.

Cheers!
T