Blue Planet Tank Maid Internal Filter Pro 400 The Blue Planet Internal filter sit inside your aquarium, they contain sponge and charcoal, but you also have the option to fill with noodles and other filter media. Attaching airline to the outlet of the filter will draw air in creating a stream of bubbles from the filter. 400L/Hr, 70cm head height. For 40L Aquariums Flow rate is not adjustable. Power usage 6watts. Available in a variety of sizes to suit different species and tank size Great for removing excess dirt or additional filtration when you have large fish that are starting to outgrow their current home.