MY DIY FUGE + some questions

[bededog]

Here is a picture of what I have planned for my fuge. I am going to put it in a closet on the other side of the wall from my tank. I am going to put it a little higher than the main tank so I don't have to worry about overflow boxes etc... I want to just have it overflow into my tank and pump water back into the fuge via a pump in the tank. Tank is 46g and fuge will probably be a 20g long tank if I can drill one without shattering it. My questions are:
how big should I make the hole for the overflow?
how many GPH should the pump be?
Is my plumbing on the intake ok with a turn at the bottom?
Do I need the baffle(s)?
I plan to have it drain from the top, is that OK or should I make it just like pre-drilled tanks are done?
Do I need a check valve or anything else on my plumbing?
What shoud I do with the pipe going back to the tank, should it just be straight or have a turn at the bottom?
Also, the skimmer is a HOB Prizm Deluxe and I will be putting my heater in it and lighting it.
I know I have listed a lot of questions but I want to do this right the first time. If anyone wants to take the image and correct/add anything, feel free.
If the people on these boards ran the world I believe it would be a much happier planet. Everyone is so helpful.

 

[bang guy]

Hi fellow Brookie Angler!
I see no purpose for the baffles on the intake side. I see benefit to having a single panel on the overflow side though. Can you drill this thing on the bottom? Near the bottom will also work.
Building an internal overflow has a LOT of advantages. You'll find that an overflow as you have pictured needs a really big hole to move very much water and it's prone to clogging by a loose piece of algae or a big snail.

 

[bededog]

Thanks for the quick help Bank Guy. Hey, I am in your neck of the woods this week or at least somewhat. I am near Rochester visiting the in laws for the Holiday.
I guess I will try to drill it on the bottom. Anyone ever tried to drill a glass aquarium?

 

[bang guy]

If the bottom is tempered you'll have to drill it on the side. This is when an Acrylic aquarium is reall nice.