How to Plumb a Dual Return?

sundog101 · Nov 4, 2021

I’m looking into getting dual return pumps for added redundancy, but I’m a little confused on the plumbing. From what I’ve read, having 2 separate lines would be best. However, I’m leaning away from that as I don’t want to reconfigure a ton of plumbing. I would like to plumb the 2 pumps into a single return line. From what I understand this can be done:

a) In parallel with check valves
b) In series

I like the in series option, but would this do anything for redundancy… or is that just for increasing head pressure? Also, I’m I missing any options or do you have any suggestions? Thanks!!

outhouse · Nov 5, 2021

So it all depends on what type of pump you run. If you run a DC pump use a large pvc size like 1 1/4" that goes goes up top a Y fitting and send water to your 2 different returns from one pump using 1" then use a reducer as most tanks have 3/4" internal size for each.

the larger size pipe helps increase flow for DC pumps. For a high energy usage AC pump you can run 1" to a T Same for drainage 2 into 1

MissingYuengling · Dec 30, 2021

sundog101 said:
I’m looking into getting dual return pumps for added redundancy, but I’m a little confused on the plumbing. From what I’ve read, having 2 separate lines would be best. However, I’m leaning away from that as I don’t want to reconfigure a ton of plumbing. I would like to plumb the 2 pumps into a single return line. From what I understand this can be done:

a) In parallel with check valves
b) In series

I like the in series option, but would this do anything for redundancy… or is that just for increasing head pressure? Also, I’m I missing any options or do you have any suggestions? Thanks!!

Bump

YOYOYOReefer · Dec 30, 2021

Go series. parallel the pump heads need to be exact matches or its detrimental.

YOYOYOReefer · Dec 30, 2021

better answer parallel will get you more pressure if thats your end goal, series more flow...

im used to much higher volume pumps for chemical plants,... at the aquarium level the parallel being detrimental is not really true, its not gonna be a factor unless you have a swimming pool sized pumps or bigger.

MissingYuengling · Dec 31, 2021

YOYOYOReefer said:
better answer parallel will get you more pressure if thats your end goal, series more flow...

im used to much higher volume pumps for chemical plants,... at the aquarium level the parallel being detrimental is not really true, its not gonna be a factor unless you have a swimming pool sized pumps or bigger.

What about if I want two pumps going into only one return in an internal overflow? A tee-intersection going into the return line?
Thanks

AJsReef · Dec 31, 2021

MissingYuengling said:
What about if I want two pumps going into only one return in an internal overflow? A tee-intersection going into the return line?
Thanks

T works, wye fitting would limit losses. You’d need functioning check valves to ensure if one fails the functioning pump isn’t just taking path of least resistance back to the sump.