Internal aquarium filters

An internal aquarium filter helps trap suspended particles and houses the bacteria used for biological filtration. Discover our OASE BioPlus, Superfish Aqua-Flow, and other filters for freshwater aquariums.

How to choose your internal filter?

• Aquarium volume: choose a model sized for your tank and its inhabitants.
• Actual flow rate: take into account the filter media and flow losses during operation.
• Filtration: check the sponges and media provided, as well as how easy they are to replace.
• Size: check the filter's dimensions and the space available in the aquarium.

Internal or external filter?

An internal filter is installed directly in the tank and is suitable for many compact setups. An external filter frees up space in the aquarium but requires installation with tubing. Compare the equipment based on your project.

Frequently asked questions

Should the sponges be cleaned during every water change?

No. Only clean them when necessary, preferably in water taken from the tank to preserve as many beneficial bacteria as possible.

Is the stated flow rate enough to make a choice?

No. Volume, the number of inhabitants, the media, and actual operating conditions also matter.

Discover our external filters, our Superfish filters, and our filter media.