Plumbing help

[SapperReef]

Hello everyone,
So I bought a tank off a buddie and it came with a duo corner over flow. It came with all the plumbing but he had it up for years should I still use it ?? If not it’s okay I wanted to change the color of the plumbing anyway and see if y’all can suggest best way to make it quiet!!
I never plumbed a tank before I always had AIO and I done some research but seems like there’s a lot of ways to plumb a tank but I see a lot of people use 1” for over flows and 3/4” for returns is this corrects ? So I will need both bulkheads and 90s and gate vale’s in those sizes ??
If y’all need more info lmk sorry kinda of a newbie to this

 

[tbasinger]

I always use an overflow that’s twice as large as the return, i’ve built a lot of tanks and found out the hard way of having too great of return and not enough drain.

 

[SapperReef]

I always use an overflow that’s twice as large as the return, i’ve built a lot of tanks and found out the hard way of having too great of return and not enough drain.

So go 11/2 drains and 3/4 returns ?