Are you talking about the LX-2000s (this one: http://www.coralvue.com/reef-octopus-lx2000s-protein-skimmer)? I'm sure there will be a few here who have used it. Assuming this is the one you're asking about, it looks like it maxes out at 150g per the manufacturer. I probably would try to find something larger for 150 gallons. I usually prefer to oversize my skimmers by quite a bit, and most hobbyists will generally say to get one rated for around double what the manufacturer's specs state (this varies by brand, but I find it far better to overskim than underskim).