hey mario, i actually was going to go with an asm g4x, but i'm not a huge fan of asm. they are rated for like 400 or 450 gallons, but with asm, i hear you have to cut their ratings in half to get a good operational capacity.
the octopus i used was the dwn-150 (recirc) on my 90. right now i'm using a euroreef rs250 on my 180 and that thing is a champ. the only problem i have is that my water level is 4" too deep for an in-sump skimmer, but despite that, i get good skim from my euroreef.