For alternate cleaning. If sponge is the only media available for your internal filter it is tasked with performing the roles of both mechanical and biological filtering. The sponge needs frequent cleaning, yet cleaning risks the bacteria colony. The solution is two sponges, so that they can be cleaned alternately, or even replaced alternately, and the bacteria remains intact. In most situations, an external filter would be the better choice. Canister, power filter, wet/dry sump, refugium, all have the advantage of not taking up any space inside the fish tank. They are also all capable of holding more media than internal filters. However, some situations make it difficult to install an external filter on a fish tank. For example, if the tank is located in such a way that there are no available spaces behind, nor at the bottom, then your only choice might be to use an internal filter. For simple biological filtration, an air-driven sponge filter would suffice. However, a pump-driven internal filter offers increased circulation and better mechanical filtration.

There are many choices out there when it comes to filtration for your fish tank. Which of the many choices out there would make the best choice for you? Internal, or external? Are you looking for supplemental filtration, or primary filtration?

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It can be used as a lone filter or with other filters for extra filtration and water movement like I use it. Mine has been running for about 7 months now and it is still as strong as ever and continues to be completely silent. It has 3-stage filtration with foams, BioMax rings and Carbon included as standard. You can find replacements for these relatively easily either from your LFS or online. This change of mind return policy is in addition to, and does not affect your rights under the Australian Consumer Law including any rights you may have in respect of faulty items. Depending on the type of fish that you keep, you are either going to want slow or fast flow and a flow control that is simple but effective. The filter provides the option of setting the flow output in 3 different positions, a key benchmark in underwater filtration. The adjustable 3-way flow control feature lets you position the water flow output to meet your specific needs. The Top Output setting provides maximum circulation and oxygenation, the Integrated Spray Bar setting provides a gentle, even flow for planted aquariums, and the Bottom Output setting is for deep water agitation. The ability of some filters to take extra media is a feature that has definitely come to the fore in recent years. The more media the better, as it means more cleaning power and more waste reduction power.

Large pallet items like aquariums are deemed delivered successfully with no damage once the the driver has left the property. If a report of damage is submitted after the driver has left we may be unable to assist with replacements. We recommend refusing a damaged delivery, this is the fastest resolution. Not much really, other than the flip-top was a bit stiff on our new model and impeller access isn’t as accessible as it was on the previous Fluval plus model. The Fluval U2 Underwater Filter provides complete and efficient 3-stage filtration, including BioMax biological filtering, to create superior aquarium water quality. The U2 Filter includes practical and versatile features, making it ideal for application in fresh, marine and reptile environments. If your filter fits into the rear corner you may not want a water flow that is only unidirectional. Having the option of being able to direct the flow left to right and/or up and down gives greater flexibilty and is a function easily achieved by the manufacturer at little cost.

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Carbon inserts have visible benefits as they remove dyes from water, odours and traces of medications. They remove chlorine too. But, for me, the best media option of all is extra biological media. As with the double sponge scenario, one doing the mechanical filtering and leaving the other to do the biological filtering, is better than one media that is tasked to do two jobs. In my book, extra biological means a better filter. Offering outstanding 3-stage filtration, with increased water movement and vital aeration, Fluval U-Series internal filters are the perfect solution where external filtration is not possible. An internal filter would not be my first choice. However, I was faced with a situation that would not have allowed the use of an external power filter. My choice then came down to between an internal vs. a canister filter. The tank will contain floating plants. Circulation needed to be gentle, and the surface of the water should be still. This filter met the requirements, without the maintenance hassle of having to use a canister filter. Fluval U series filters provide the option of setting the flow output in 3 different positions, a key benchmark in underwater filtration. The Adjustable 3-Way Flow Control feature (available in the Fluval U2, U3 and U4 models) lets you position the water flow output to meet your specific needs. The Top Output setting provides maximum circulation and oxygenation, the Integrated Spray Bar setting provides a gentle, even flow for planted aquariums, and the Bottom Output setting is for deep-water agitation. Fluval U Underwater Filter provides complete and efficient 3-stage filtrationto create superior aquarium water quality. All models come with a Bio-Foam filter pad to remove large particles. The larger 2 sizes also include a Poly-Carb pad to assist with removal of fine particles, chemicals and odours. They also have the addition of Biomax filter nodes to assist with biological filtration.