What size plumbing for DC 10000ii return pump

scerdoc · Mar 3, 2014

As the title says I have a new Waveline DC 10000ii pump to use as my return from 40 gal sump. Output of pump in 40mm (1.5 inches) and tank (135 gal) is pre-drilled for two 3/4 inch returns.

Question is - does it matter what size line I run from the pump to the tank? Obviously will need to be stepped down to 3/4 inch at the tank if use larger from the pump. Also I know the 3/4 size is flow-limiting...just wondering what people end up doing.

Thanks in advance!

bearjohnson · Mar 3, 2014

I'd run 1-1/2" as close to the two returns as possible and then tee of to the returns with 3/4"

By running it full to as close as possible you'll maintain the water volume whereas if you tried to run just 3/4" straight out of the pump and then to the returns. Make sense? LOL

scerdoc · Mar 3, 2014

That's what I was thinking I should do, but my first tank so wanted to bounce it off those with experience!

AJsTank · Mar 3, 2014

I use 2 of the DC 10500 Reef Octopus pumps (not sure which waveline that is) on my 400. I run them at 80% and use 1 inch returns on the lines and it works great.

Bad Company · Mar 3, 2014

Pump flow is a function of head loss. If you really want to maximize flow going from a 1.5" dia pump output to two 3/4" returns , try to eliminate the following:

- ball valves (use gate if necessary)
- check valves
- sharp 90Â° elbows (use sweep if necessary)
- head height (the difference in the two water levels from the sump chamber to the dt water level)
- in your "T" consider a 1.5" X 3/4 X 3/4 "Y" fitting
- Use a section of reinforced flexible tubing off your pump for noise reduction

All in all, the geometry of the 1.5" piping is not that important because the fluid velocity there will be 1/2 of what it is in the 3/4" tubing. Center the "Y" between the returns of you'll have to use a partially closed valve to get even flow.

GL!