which one do I get?

This is for my new 75 gallon sw
After reading on this forum and reviews at different online stores I decided to get the AquaC Remora Pro hang-on skimmer. But there are several different ones. I have never owned a skimmer and I don't know how they work. Which one do I need? and why?I can only assume that the most expensive one is the best but thats not always the case.
Is the surface prefilter box necessary?
Please and thank you!

AquaC Remora Pro Protein Skimmer with Mag 3 Pump & Drain Fitting
AquaC Remora Pro Protein Skimmer with Mag 3 Pump
AquaC Remora Pro Protein Skimmer with Rio 1400 Pump & Drain Fitting
AquaC Remora Pro Protein Skimmer with Rio 1400 Pump
AquaC Remora Protein Skimmer with Maxijet 1200 Pump and Drain Fitting
AquaC Remora Protein Skimmer with Maxijet 1200 Pump
here is the link for these skimmer
AquaC Remora Protein Skimmers Aqua C Remora Reef Aquarium
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reef4girl

 

id go with the AquaC Remora Pro Protein Skimmer with Mag 3 Pump & Drain Fitting, when i got mine i didnt get the drain fitting cup and I deff regret that but no the prefilter box is not necessary but it does help with the micro bubbles

 

also if you do get the prefilter box you have to make sure you water lvl stays the same so the pump doesn't run dry

 

thanks rusty

 

no problem

 

anyone else want to chime in

 

I would agree and get the mag4 pre filter and the drain line.

I don't see a sump listed in your sig line. You are going to need an ATO if you want to run the surface skimmer.

 

+1 with Horkn

 

what is an ATO
no sump

 

auto top off

it is not necessary to use an ATO with a skimmer, but using the surface skimmer attachment will make the water level get low quick in that surface skimmer and possibly hurt the pump.