Closed Loop Drilling for a Perfecto 120 Gallon?

[Drgonzo399]

Hello everybody. OK, I'm new at reefing and have a 120-gallon (perfecto) tank locked up. This will be my first tank, and I (believe I) want to install a closed loop system and horizontal overflows for a sps setup to maximize water flow. I was wondering if anyone had a similar tank or had any recommendations on where to drill the holes and why. Obviously my seller wants to get the tank out of his house so I am hoping to get a quick answer here.

This is what a friend had to say:
I would definitely get a closed loop, and maybe a horizontal overflow on a tank that size. The horizontal "calfo" overflows should just be two holes in the top, I think at about 1/3 and 2/3 the length of the tank but dont quote me. Maybe four holes on the back wall 8 and 16 up the glass for closed loop.

The way I see it though if you have more holes than you need you can just cap them up. If you have less than you will have to get creative since you cant drill if the tank is filled.

Thanks in advance for any/all info., ~Mike

[AllenFord_SC]

Drilling for a closed loop is all dependant on where you want your outputs and drain(s). Some people drill in specific locations that they have determined to hide all plumbing behind rockwork, while others drill the bottoms of their tanks for closed loops to keep detrius suspended in the water column. I guess what I'm saying is, drill em' where ya want em'.

[fishaholic911]

Is the bottom tempered glass? If so you can not drill it.