Thanks guys for the info...Actually, I am looking to upgrade my current Atman II PH-2000 Skimmer (35W, Hmax:2.2m, Qmax:2200L/H) for my current tank (4ft x 2.5ft x 2.5ft) together with est 3 ft Sump (W18.9in H21.65in L30.71in).
The livestocks in the tank are 1 Powder Brown, 1 Yellow Tang, 1 Sailfin Tang, 1 Blue Tang, 2 Red Anthias, 1 True Clown, 1 Clark Clown, 3 Purple gobies, 1 Six Line Wrasse, 1 Purple-back Dottyback, 1 Gold-Rim sand Goby, 1 Comet, 1 Banded Sole, 2 Camel Shrimps, 1 Fire shrimp, 1 Cleaner Shrimp, 1 Blue Boxer Shrimp, 2 ###### Shrimps.
Some Corals include 2 Bubble, 2 Octos, 1 Frogspawn, 7 Acros, 1 Elegance, 2 Clams, 2 Buttons, 2 Zoos, 2 Candy Cane, Brains, Flower-pot coral, Mushies, etc.
I think my current skimmer may not be working 'hard' enough as I don't see too much residues (usually wet) in the collection cup even after 2 days.
So I am considering to upgrade to either AquaC or MACRO.
Please advise.