Hi 1st just the sponge , 2nd the skimmer(stock) and within the 1st few days I emptied it as it was full of crap) 3rd got bio balls , those ceramic noodles , charcoal mixed with small white stuff and heater and 4th my return pump and uv light.At the momemt got some 4 kg lr and some pieces of bio rock.Need to test it this weekend .give it time i'm sure all tanks are different in one way or another good luck.