I'm wanting to do a setup with two displays, attached to a single sump. I've got a 40 for the sump, a 40 for one display, and a 75 for the second. I've plumbed several tanks myself previously, but always single displays to a sump.

Would it be better to just have both tanks plumb separately into the sump, with two returns, or have a single return with one DT flowing into the second DT, then into the sump and back? I'd be building my own stand, which I've done for all of my tanks except for a 210, I'd account for space in the sump for emergency overflow from both tanks, but I'd rather not do two returns, if only to save on power. The return pump I'm currently using is a Vectra S2 (pretty sure it's an S2, I've had it for years). I' not concerned with flow from my return so much as just making sure the flow works.

Any help or ideas would be appreciated.