Where to drill a 180

[ktg113]

I am in the process of putting together a 180 peninsula with the beananimal over flow and I have Three questions

1 how deep and wide do I need to make the overflow box

2 once the box level is set how far from the top should I drill them

3 I want to install a closed loop and was wondering where I should drill the holes I was going to drill center bottom for the closed loop I have two rocks that I can cover the pipes with I was thinking (1) 1 in drain and (4) 3/4 returns making a square one facing each corner and the drain in the center of them

Any ideas will take in to consideration thanks

 

[koralkrab125]

im having a problem understanding what kind of overflow your going to use, but the first thing i see is having a drain that is only 1 inch i would do 1 1/2 inch drain

 

[ktg113]

It will be a coast to coast running along the top and the bulk head will be 1 in but piping will be a 1 1/2 in running around 3000 gph quite and fail safe. After all the reading I have done on the beananimal overflow it will be the only one I ever install fairly simple can handle large volumes and quite