UV help

Looking for a UV for mu 40 breeder, bare bottom. Was looking to get a coralife turbo twist. Should I get a 18 or 9watt? Are there reasons I should or shouldnt get a 9 or 18 watt?

 

9 watt would be plenty,I have seen a visibly noticable improvement with mine,not to mention all the stuff you don't notice,my corals have improved greatly and film algae is practically a thing of the past.Mine is built into my canister filter and is only 5 watts on a 55g.Proper flow through them is a big key to them doing thier job correctly.Too much flow,and theres not enough "contact time" with the uv light to kill algae spores,other certain pest spores and parasites.

 

I was planning on running it with a venturi mag drive 7 inline to my protein skimmer. What do you think about that?

 

Plumbing wise it would work,but i would have the uv tee'd on it's own loop with an adjustable ball valve to reduce flow through the uv.