Turbosek

I am planning to use an Aqua-C EV-240 skimmer on my new 162 gal reef tank. I see that you can buy them with either a submersible pump or an external pump. If run with an external pump, does the skimmer then sit outside the sump?

Also, I would then need to runa separate external pump for the flow through the sump and fuge...correct. Do I factor in both pumps for total flow rate in tank?

I also hear of a lot of people running 2 return pumps, in case one goes bad, you have ...

Just wanted to say Hi to everyone. I just signed up to Reef Addicts. I have had a 37 gallon FOWLR tank for 8 years. I just decided to step it up to a 162 gal in-wall reef tank. I just ordered it, and am preparing the wall and room behind. I will be making lots of posts and pics along the way. Since I am new to reef tanks, and advice will be helpful!

First question...what skimmer should I buy, and why? I will have a sump section for the skimmer. Have not built the sump yet.