Plumbing question

I am in the process of building a 125 with one built in overflow. I have a question on piping now. I got a 55 for my sump and an octopus reef 150 skimmer but my return I purchased a mag18. It has a 3/4 return line and my tank is drilled for 1 inch return. Will it be ok to run 3/4 to the bulkhead and reduce it there?

Also my overflow to sump is plumbed at 1 1/2 inch. I only have one overflow built in and I will be building the overflow pipe inside. My question is there is not alot of room inside for this size pipe with the overflow I am creating. Will it be a problem to plumb this in 1 1/4 to the sump? I will install a ball valve on the return to throtle the return if needed?

Any help would be great. Thanks

 

the folks at reeflo told me that all pumps sold today should have oversized piping coming off the output or you are not going to get the output that the pump is rated for. I'd upsize the plumbing coming off the pump to 1" and run 1" all the way back to the tank.

You can run the overflow at 1 1/4 but definitely include the valve on the return. Smaller piping on the overflow can increase the noise level. Also look for a return pump that is designed to use less electricity the more head pressure. The Sequence Reeflo Tarpon and Wahoo I believe fall into this category. Most pumps will use more electricity if you valve down their output.

 

check the spec on the MAG18, even though it's output is only 3/4 they recommend a bigger line. I only have a MAG9 and I'm using the recommended 1 1/4 PVC for the return for maximum flow. When I was building the system I called the mfgr, I explained that the bottle-neck would still be the return line hole on my build-in overflow box but they said I should still go with 1 1/4...PVC is cheap so I went with it and I get a lot of flow from my MAG9.

On my overflow line I'm running 1 1/2 PVC

 

I think I will go with 1 inch return and 1 1/2 overflow. Thanks for the input.