Expecting based on what?
The Quiet One 3000 appears to be rated for 758 GPH with nothing connected to it, and it has a 1" outlet that has been reduced to 1/2". Not ideal.
Based on the flow curve, and assuming your return is about 4-5' over the sump, it looks like the most you could expect under ideal circumstances is about 500 GPH.
When I
look at a friction loss calculator to see what effect the 3' of half-inch plumbing has, I get +1.5' of head pressure:
Pressure Loss (psi): 0.65 Head Loss (ft): 1.5
Line Number: .5" @ 3 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.5
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.622
Fluid Velocity (ft/sec): 8.45
Reynolds Number: 41693
Flow Region: Turbulent
Friction Factor: 0.023
Overall K: 1.32
Piping Length (ft): 3
The lower section of your plumbing appears to be mostly three-quarter inch or half-inch vinyl tubing. Assuming that's 3/4" tubing on the pump, and that's about two feet in length, it only adds +0.3' of head pressure:
Pressure Loss (psi): 0.11 Head Loss (ft): 0.3
Line Number: .75" @ 2 feet length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 0.69
Piping Length (ft): 2
The middle section with one-inch PVC for the elbows and reducer would look something like this, adding +0.7' of head pressure:
Pressure Loss (psi): 0.3 Head Loss (ft): 0.7
Line Number: 1" @ 1 foot length
Date: 10/12/2017
Nominal Pipe Size: 0.75
Pipe Schedule: SCH 40
Flow Rate (gpm): 8
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.824
Fluid Velocity (ft/sec): 4.82
Reynolds Number: 31472
Flow Region: Turbulent
Friction Factor: 0.024
Overall K: 1.9
Piping Length (ft): 1
Short Radius Elbows: 2
No. of Reducers: 1
Reducer Outlet Size (in) : 0.5
The total added friction loss from the plumbing would be something like +2.5'.
That takes your pumping height from 4-5' without friction loss.
Including friction losses, that pumping height goes up to 7-8'.
Referring back to the flow curve, you might only be able to get into the neighborhood of 250 GPH with this configuration.
What
@jeff williams said.