Manifold before or after check valve?

[Noireatsbear]

Sorry for stupid question. But should yhe check valve go before or after the manifold from the return pump?

So, return pump, manifold, then check valve
Or, return pump, checkvalve then manifold?

Thanks!

 

[tsouth]

The check valve should be at the very top, nearest the bulkhead/turn. You want to stop the flow of water at the highest most point to reduce the amount of backflow.

The one caveat I would see here is that you have multiple return lines being supplied by the manifold therefore you may:
1. Need a check valve for each return nearest to the bulkhead
2. Using the manifold to serve all returns, thus saving costs and putting the check valve before the manifold

Keep in mind that check valves were expected to be serviced if i'm not mistaken, therefore reachability is important.

PS. Nothing to be sorry about - this is a legitimate concern that I have also searched for in the past. Hopefully this post helps the next reefer too

 

[Noireatsbear]

The check valve should be at the very top, nearest the bulkhead/turn. You want to stop the flow of water at the highest most point to reduce the amount of backflow.

The one caveat I would see here is that you have multiple return lines being supplied by the manifold therefore you may:
1. Need a check valve for each return nearest to the bulkhead
2. Using the manifold to serve all returns, thus saving costs and putting the check valve before the manifold

Keep in mind that check valves were expected to be serviced if i'm not mistaken, therefore reachability is important.

PS. Nothing to be sorry about - this is a legitimate concern that I have also searched for in the past. Hopefully this post helps the next reefer too

Thank you for the advice! this will save me a bunch of time trying to route my plumbing in the tight space that i got from my already small Trigger Systems 18c to my crappy petco stand. Hehe

 

[K7BMG]

Check valve placement is not a stupid question.
There is not a one size fits all here.

Also check valve construction can make a difference to where it should be located.
Flapper type require more head preassure to make a proper seal.
Spring loaded not so much.

The check valve is a safety stop so water does not flow where its not wanted.

So in the simplest term what is it for mainly.
To prevent back flow to what?
The valve should be placed as the first fitting after the what.

If you have a line from the manifold into a reactor and from the reactor into the display tank, then that line could siphon and drain the tank and overflow the sump.
So it would need to be installed between the pump and manifold to prevent an overflow.

So dependant on your situation its location could be anywhere.

As far as your main display goes the weir and or other lines should not be placed in such a manor that would allow the water to be syphoned out more than a few inches anyway. Thus everyline will break the syphon without the need for a check valve.

 

[Futuretotm]

Sorry to hijack your throat. What about not putting a check valve. Once enough of the water from the display tank siphons to the sump the siphon will break. Of course this assumes you have enough capacity in sump.

 

[K7BMG]

Sorry to hijack your throat. What about not putting a check valve. Once enough of the water from the display tank siphons to the sump the siphon will break. Of course this assumes you have enough capacity in sump.

Yes thats right, only if thats the design of the system.
Not all systems are built this way.