I have a 60 litre Nano cube Orca 450tl (16 US Gallons)with 2 Red leged hermits, 2 Percula clowns, a Red Scooter , a Flame Hawkfish and a cleaner shrimp they seem to be doing well, I do have about 8 Kilogrammes of live rock and the Nano cube does have a skimmer which may help.
I would think if...