I think I have my 120G build set for about 165G total system volume with the sump. I was looking at the eheim compact 5000 pump. Adjustable from 660-1320 GPH. That should give you what you need. Since you live in Canada have you looked into the SWC skimmers at all?
Xtreme 180 conical protein skimmer.
The ORIGINAL Xtreme protein skimmer! Comes with a Sicce psk 2500 pump.
An integrated removable bubble plate to help reduce turbulence within the protein skimmer.
Fully disassemble, due to the removable base plate.
Perfectly balenced body and neck.
Adjustable air intake for fine air flow adjustment.
Gate valve pipe output allows you to adjust the skimmer and have precision control of the water level.
Custom pin wheel impeller. 900-1100 lph of air pull using custom impeller. Air number will vary depending on aquarium set up and testing methods.
These are real numbers not hyped numbers. Draws less than 25 watts of electricity per pump.Quick release neck on the collection cup - requires 1/2 inch of clearance to remove the cup.
In sump skimmers only.
Recommended water depth 7-9 inches.
Foot Print:
LxWxH in inches
9*8*21
Xtreme 180 cone Skimmer
Light Bioload
Medium Bioload
Heavy Bioload
Tank ratings
250
200
150