The EHEIM aqua is a multi-functional internal filter with compact dimensions and a clever modular design.

EHEIM aqua is a very easy to use internal filter for small to medium-sized aquariums. Ideal for beginners, it is simply attached to the corner of the tank with suction cups. Due to it’s compact size it takes up minimum space in the aquarium and leaves plenty of room for aquascaping. The powerful pump and large intake area ensure efficiency and the output can be easily adjusted to regulate both the water throughflow and the surface movement. In addition, a diffuser enriches the water with oxygen. The main feature, however, is the modular design: The filter containers can be easily removed for cleaning and, if you want to increase the filter capacity, you can extend it with additional canister modules.

This is for the Eheim Aqua 160 filter