Yea i did that on 2 walls so 1 wall has 9metres of tanks and the other has 6 metres of tanks and then the other 2 walls i've got my planted tank (5FT) and oppisite that ive got my fry tanks under the window.
My mum was happy that she got a spare bedroom at last and then i had a great idea lol
Make sure you keep the curtains closed during the day and then open them abit a night to get less condensation. also keep the door and window closed to keep the power bill down