UV Sterilizer Question - Flow Rates

[ASpec]

I'm about to purchase a UV sterilizer for my tank. I plan to plumb it with my canister on the return side.

The canister is rated at ~280gph... most of the 9w UV's I am looking at (CSL's Double Helix and the Cora Life Turbo Twist) are rated at 200gph max flow rate. Do I need to consider going with an 18w UV ?

I understand a UV sterilizer is not effective if you exceed the max. flow rate so I want to make sure I get the proper size.

Thanks!

 

[scuba_steve]

imo i wouldnt waste the money on one myself !! there are better ways to keep your tank