Can anyone suggest an in sump skimmer for me?

[snow1]

Hi all, I'm looking into different skimmers for my tank. I really like my vertex that I have on right now but it's only good up to tanks that are 80g. I'm looking for options on a skimmer for a 175g tank. I really like vertex ones but when I looked at the higher end models the price really jumped. Plus I have a space issue. The skimmer can't be wider than 12" or it won't fit in my sump. and it can't be over 20" in height, is there a skimmer out there that would fit? I don't want to spend like $700 on a skimmer b/c I new to saltwater and just want something to get the job done. I know you get what you payed for etc... but what's a good choice? The tank is going to be a moderatly stocked predator tank with fish such as eel,groupers etc....
OR
do I even need a bigger skimmer? I know skimmers are not needed and the filtration on my tank is already very good. Seems to be going well so far but the tank does not have any fish yet.