Where to drill my tank?
 

I have 1" bulk heads, 75 Gal tank with black trim.

In relation to the black trim at the top, how far down should I be drilling my holes?

1 suggestion I have heard is the middle of the hole 3" below the trim. Anyone else agree/disagree?

I don't have an overflow box as of yet.

I'll be plumbing a Bean Animal.

I would go at least 2" to the top of the hole from the trim. On my own tank I'd probably go 6" to center for piece of mind.

If I remember correctly, the correct measure is 1 1/2x the hole diameter from the edge and 2x the hole diameter from another hole.

If it were your tank how long would you place the holes? I need to take into account the elbows for the drains for the BA overflow.

Are you thinking of doing an internal or external overflow?

Internal