If you have enough LR
, no extra filter is needed, just circulation in the main tank in the form of powerheads. (a pair of Maxi-Jet 1200s or a single Seio powerhead could provide enough flow unless you have tons of corals).
Stay away from Prizm and Seaclone skimmers. Good brands include AquaC (Remora if you don't have a sump, Urchin if you do), ASM, Deltec (expensive).
Do you plan on keeping any corals? If so, lighting is very very important. If not, anything will really do.
55g reef, 2x250W 10k MH
+ 2x96W PC
actninc, 10g sump, AquaC Urchin skimmer, 65lbs LR
xenia, mushrooms, wels. open brain, fungia radiata (orange), green eyed zoos
flame angel, mated pair of false perc, 6-line, firefish
20gH electric yellow cichlid