This is a classic background which covers only the back glass of the aquarium and has one chamber for the suction pipe and heater. The chamber can be placed in the left or right hand corner. The heater and suction pipe should be placed together in the chamber, to avoid a difference in temperature between the chamber and the rest of the aquarium. Water enters the chamber through a space between the glass and the background. This entrance goes all the way from top to bottom and is covered with a plastic transparent mesh that stops smaller fish entering the chamber. Standard dimensions of chambers are 8x8cm or 10x10cm. The freshwater outtake is to be placed over the background.