As some of you know my 40 gal. Breeder project is almost done I bought Return Pump as last piece to finish… I decided to buy new version of Jebao DCT 4000 which max flow is little over 1000 gal/hour. But Im confused now. Either pump is defective or…. no idea. Pump has 10 speeds but on full power it is still little flow in the tank. I don't know whats going on. I have a 3/4 PVC return pipe split with tee and then pipes go to two corners. Nothing fancy just regular plumbing. I will try to return it and get 6000. Will see if I can do it. So Im back on market for Return Pump. Any idea what I did wrong? thanks.