How to Choose the Best Filter for You and Your Tank

You've invested time and money into creating the best living situation for your fish by purchasing a beautiful fish tank, thoughtfully curating the types of fish that live together, and adding decorations that match the room's vibe and your personality.

Providing a healthy environment for your fish with clean water is the most important aspect of aquarium maintenance. While you might think you have that aspect taken care of with your filter, aquarium maintenance isn't a completely hands-off operation. Even after you've chosen the best filter for you and your tank, you still need to test aquarium water every week.

What does a filter do in a fish tank?

A filter keeps water clean and fresh by removing debris — physical (from fish waste and food particles) and chemical (like ammonia that comes from fish).

There are three stages of filtration critical to maintaining a healthy aquatic environment for your fish and aquatic plants:

  • A biological filtration system decomposes ammonia toxicity from fish waste by converting it to nitrate.

  • A mechanical filter, like the Aqueon SmartClean Power Filter with EcoRenew Filter Cartridge, traps particles and debris on a fibrous or sponge material, which is then removed from the aquarium when the media is rinsed or replaced.

  • A chemical filtration system removes dissolved waste by adding chemicals that dissolve in the water. Carbon, in particular, can help remedy the greenish or yellow tint.

Many aquarium filters take care of all three stages but usually perform better in one or two.

Need to brush up on filter know-how? Here's everything you need to know about filtration.

What's the best filter for my aquarium?

You have a lot of options when it comes to filters. Consider the following as you look for the best filter for your aquarium:

  • Tank size. Ensure the filter is recommended for your specific tank's volume so you don't under-filter or over-filter the water.

  • Bio-load on the tank. It's important to think about the size and number of fish in the tank and how much waste they produce, especially those that eat more times a day and with larger fish in the same space.

  • Easy maintenance. Look for a filter that's easy to access in the tank, which makes it simple to change cartridges, and one that makes water changes a breeze. (See next section for how a filter helps with water changes.)

  • Environmentally friendly. Look for an aquarium filter that uses cartridges made from natural fibers and infused with activated carbon for effective sustainable filtration, like the EcoRenew for the SmartClean Power Filter.

  • Flow rate. Factor in the type of fish and plants in your aquarium as you select a filter that works with your fish and plant species. Delicate plants need a gentler filter flow than hardier plants. Some filters, like canister filters, might produce a stronger current and benefit fish preferring that speed. Fish with more delicate fins, like betta, will need a more gentle flow than a fish like a danio. Ideally, the flow rate of your filter should be between four and six times the size of your tank.

  • Sound. The sound of bubbling water can be calming to some aquarists. If you prefer a quieter option, look for a quiet power filter.

  • Desired Water Level. If you want to maintain a lower water level in the aquarium, an internal filter that suctions to the side will sit lower and be quieter than a hang-on back filter that sits or hangs from the top rim.

How does a filter help me change the water?

Fish tanks aren't "set it and forget it"  ecosystems. While a filter helps clean the water in your aquarium, you'll still need to change the water occasionally. (We suggest about 10 percent of the aquarium water every week.)

Aqueon's SmartClean Technology filter makes it ridiculously easy to remove up to 25 percent of the tank water while the filter is attached to the aquarium. Rotate the water discharge arm to remove the water and then refill with conditioned tap water.

You'll have improved water quality and a cleaner aquarium in minutes.

Now You're Ready to Choose the Best Filter for Your Tank

Choosing the best filter for you and your tank is easy when you consider your fish and your tank's needs. A hardworking filter should have a flow rate at least four times the volume of the tank per hour to keep the water clean. If your tank has fewer fish or fish that don't eat as much food or as often, a filter that runs the water through at this rate should do the job fine.

Remember to change at least 10 percent of your aquarium water every week, even if it looks clean and the test strips say it's fine. This will help keep your tank's ecosystem operating optimally and help keep fish healthy.