Squire's 90 Gallon Build, Now With Salt Water

[ensquire]

Issue #3) Sump flow, I know the goal that all drain water should run through the skimmer before going to the return chamber. With that in mind I decided to see if my sump would make that possible. What I found is that either my pump is to big, or in combination with my drain problem, I can't throttle it back enough for the skimmer to handle the flow. My pump is a Waveline 5000 with 1300 GHP but I run it at half so probably 700 gph . The sump can handle full throttle but the skimmer can't. It's a SWC Cone 160. Not sure of handling capacity for skimmer . If I throttle back the drain enough for the skimmer to keep up, then the drain gets really noisy from all the air through the gate valve. So if I can solve the drain problem to some degree I can solve this one. Although I would like the most water flow thru the sump.
Can I live with not all the water not getting skimmed??
Can I mod the skimmer for more flow ?
Making this a herbie won't solve this one