I filled my tank up with cleaning vinegar and left it over night then tiped a bit out and added a cup of rice and shake the day lights out of it just dont leave the cleaning vinegar in there to long I have seen the stuff eat a 20cent piece away in a week (cleaning section at woolies normally on the bottom shelf hiden away). My next tank im going to do an electrolysis bath with 6 anodes 5 external and one internal
