gate valve or ball valve?

It is unnecessary.

Water will flow because there is pressure. If you have a valve at 1, then how are you going to get water up 4 feet to your display? It will flow 100% into your sump. You have to have it at 2. You are trying to control the amount you bypass back to your sump. What does not go to your sump will be left to go to your display.

 

WFB, that's where I would put it, at #3 like you pictured.

powerman, that's what I am trying to do. I have a mag12 coming, but my drain only flows 700GPH. So the mag12 will have A LOT more flow. By putting it at point 2 or 3, I can control how much water will go to the display. Using the gate valve, I can fine tune it to balance the drain/return flows.

 

im not sure if you are planning on hard or flexible return lines but i am going to use flexible so the "return flow valve"/plumbing would be simple. just a gate valve attached to a T attached to the back of the stand.

 

There is a 1000 ways to skin a cat. We all play with our stuff and configure it how we want. There is no "wrong and right". The Mag12 flows 1200gph at free flow. With head and piping ect you will have less. Still more than you need, but not 500gph.

One good thing is that you have enough extra to run other stuff if the need arises, like reactors and stuff. You will have the plumbing in place to hook something up if you want.

Just understsand that your tank will only drain what is supplied. There is no "balancing". You park your pump output somewhere and what ever that is overflows and drains from your tank. Water in, water out. Sorry if I'm stating the obvious, but you just supply flow, you do not "balance" drain and return.

 

Which I understand. If I put in 400gph, then my tank will drain 400gph. I just want to maximize the full potential of my overflow.

 

Exactly. Sorry for stating the obvious.

My bulkhead drain says it will do 600 gph. I increased all my plumbing to get the most out of my 9.5 (at the time). Well I actually got more than I wanted. My pump put out more than the overflow grate would flow. (There is a rating per inch somewhere)

 

I wouldn't worry about maximizing your overflow honestly, if anything it will just make it noisier (the water flowing over the barrier can make noise like a fountain if there is enough flow over it to break surface tension), just make sure you have enough flow through your sump for good filtration and that's all I would be concerned about if it were me.

 

Yes there are a million ways to skin a cat, or run a pump.

Using 1" schedule 40 PVC piping will flow 960 (or is it 980) gph. Most people don't, and won't ever need that much flow to their sumps. Unless your pump can flow more than the overflow can carry, then you won't have issues.

A 1.5" sch 40 pvc pipe can flow around 2000 gph.

 

wow, I didn't realize the 1" and 1.5" can flow that much water.