yep cheers both good sites i was right the volumes that juwel give you when you by there tanks are well out i have a rekord 96 and a rio 180 and thought that i was putting more that 96 and 180 litres into each one so i went on to the site and typed in the dimensions of the tanks the 96 comes in at 116 which is 31us gallons and the 180 comes in at 55usg now i dont have the filter boxes in either of my tanks but i know if you do still have your in your tanks you dont loose that much water as you fill that up aswell so people with juwels get your self on there and work out the correct volumes of your tanks as you may find you could hold a few more fish or you may not be as overstocked as you thought.