my tank is Acrylic there is no overflow boxes unfurtunatly,and i got my tank from a lfs it was a tank they had set up for saltwater fish and they where wonting to get red of to make more room snatched it up for 1,500 and rebuilt stand and made a canopy for it.plus it came with the filter (400 wet dry ) and he hooked me up with sand and everything else i needed must i say < i love my lfs >....