I have a Super Skimmer which I am tired of. I am planning to create a refugium, this I want a in sump skimmer. I have been looking at the ASM G3 and G4 models. I have a heavily stocked 220g FOWLR. Most of what I have read have been positive, does anyone have any imput? ALso my LFS swears that in sump skimmers are much less efficient than HOB skimmers. Is this true? ANy advise would be great. Thanks.