Tiger Flex PVC 1-1/2" whats best when...

[seasmurf]

Hi all, Thank you for reading this,

My tank(180) is drilled for 1.5" bulkheads. I think I can work with Tiger Flex PVC 1-1/2".

Is there an online source that can help me lay out my plumbing:

From over flow "herbie" (what size of gate valve do I need)

Between equipment, and for equipment mantanance purposes: what size of union fittings.

I have an idea that whats needed here is 2" joints; however, what size of barb fittings should I use?

I'm not good at plumbing. So.... help?

PS, I have observed forum pictures, Kein is especially demographic (kudos)
But I'm not 100% sure.