Thats a great deal and you won't regret a BK skimmer. But if you buy new maybe look at the BK150. It would be suited a little better for your tank size most likely. I considered the BK 180 for my 240 gallon cube with 30 fish in it. I ended up going with the BK200 which is rated for 254 gallons heavy stocked. Well according to the skimmers ability, my 240 with 30 fish is NOT a heavy stocked tank. There are some variables, fish size and amount fed but for the time this skimmer doesn't even work hard.
So in a few words, these skimmers are underrated so don't underestimate the ability of them to work.
corey