A 5-gallon fish tank has just the right volume for some basic but elegant aquascaping making it popular among many beginners and enthusiasts. Being at the threshold of the smallest size which can hold any fish, these aquariums can do quite well with a good 5-gallon fish tank filter.
Power filters or hang-on-back type of filters are the ideal devices to keep the water in a 5-gallon tank perfectly clean while also offering chemical and biological filtration. Some may want to use an external sunsun canister filter and that works just as well if not better at this size.
Most common fishes that are kept in small tanks can do well when the water is cycled 5 to 10 times an hour at a minimum. For a 5 gallon tank that translates to filters running from 25 GPH (gallons per hour) to 50 GPH.
Here are some great filters for 5-gallon fish tank capacity:
1. Penn Plax World Aquarium Filter
Popular with aquarists with small to medium-sized tanks, the Penn Plax World Aquarium Filter is a hang-on-the-back type model that is perfect for use in any small aquarium up to 5-gallon capacity. Being compatible with all kinds of air pumps, it can be easily hooked up to one and placed in the back of the tank to filter the debris and contaminants in the water.
The filter works quietly by creating an upward water current through its scrubber with the movement of air bubbles from the pump and sucks water in from the side.
The clean oxygenated water comes out of the top to keep the water fresh and clean for the fish. To control the flow through the filter all you have to do is adjust the valve from the air pump.
- Blends well in aquariums of all shapes and sizes
- Installation is quite easy and can be done by anyone
- Affordable and works reliably
- Silent and easy to maintain
- The substrate can be a bit tricky to clean as it requires vacuuming
- Chances of excess or chocked water flow when using custom media
I’ve used this filter for a few years with my 3 gallon Betta tank and it works perfectly. It’s small, unobtrusive and blends well in the tank, and even adds some good looks. I popped off each cartridge and added some ceramic media and carbon pads to improve its performance. The media get cleaned once in 2 weeks and the carbon pads get a change every 3 weeks.
2. Zoo Med Nano 10 External Canister Filter
Serious aquarists looking to maintain smaller tanks with delicate species of fish or a well-balanced environment with carefully controlled parameters need a more effective filter such as this one. Being able to take on tanks up to 10 gallons in capacity, the Zoo Med Nano 10 external canister filter is ideal for small tanks for physical, biological, and chemical filtration.
It is compatible with both fresh and saltwater aquariums and uses customizable media to get the results you desire. The filter also features a space-saving design that allows it to be stored behind the tank or inside a cabinet without having to take up space inside the tank. It comes with two output methods; a nozzle to generate a good current in the tank or a spray bar if you wish to keep it gentle.
- Ideal for perfectly controlling water quality
- Lots of room inside filter chamber for different types of customizable media
- Space-saving design that fits in any aquarium cabinet
- Works quietly without too much noise
- Comes with both spray bar and nozzle
- A little tricky for the beginner to set up
- Lacks a flow control on the filter
I’ve used this on a 7-gallon tank for a couple of months now and I’m quite pleased with the results. While it’s great for beginners there is some room for improvement regarding the media and the filter pump. After a few weeks, I found the internal sponge to be underperforming which I soon replaced with Bio-Balls and placed the sponge at the intake.
3. Whisper In-Tank Filter
The Whisper In-Tank Filter is a powerful filter suitable for tanks under 5 gallons and performs outstandingly to cycle water and keep it clear and clean for a long time.
It features a 27 GPH pump that can cycle a 5-gallon tank five times in an hour which is quite sufficient for any beginner fish tanks even when it has carnivores fish that make quite a mess.
The space-saving design of the filter also blends in well with the tank and works effectively to keep it clean. It features two levels of media which can be loaded as cartridges where one filters fish waste and debris while the activated charcoal filter removes chemical impurities, discoloration, and odor.
- Easy to use a filter that requires no setup
- Features a clip-on mechanism that securely keeps the filter in place
- Bio and chemical filtration ‘S’ type cartridges come with the pump
- Easily changeable filter media cartridges
- Fish such as Bettas could get stuck at the intake or fries could get sucked in.
It’s one of the simplest and the most elegantly designed filters I’ve come across that’s very easy to set up and use. When you first open the box you wouldn’t think that it is capable of clearing up a whole tank but it did just that on my 5-gallon tank in a matter of minutes. The intake section is quite powerful and could pick up sand particles or have smaller fish trapped at it, so I had to add a fine wire mesh. It also doesn’t need priming which is a big plus.
4. Aqueon Quietflow E Internal Power Filter
The Aqueon Quietflow E Internal Power Filter is one of the best filters out there in the market for beginners. It needs almost no setup, all you need to do is pull it out of the box, set it up in the aquarium and it starts filtering water. The filter offers physical, biological, and chemical filtration so it can be used with all kinds of the aquatic tanks.
The model fits snugly in all tanks less than 5 gallons and at a flow rate of 60 GPH can turn all the water in the tank 12 times in an hour. Another advantage is the ease with which the filter media can be accessed and changed.
The top lid flips easily and you can pull out the media for a change or customize it with your own if you are an experienced aquarist.
- Easy to use by beginners
- Fits effortlessly inside the tank and can be secured with suction cups
- The pump is auto priming so there is no need for siphoning
- The pump restarts and works normally even after a power interruption
- Quiet operation
- Small turtles can easily crawl into the outlet; however, it is no danger to them.
- Small fish can get stuck at the intake
I have used the 3-gallon version of this filter in my 5-gallon tank as I have only had a Betta and a few guppies in the for the last 2 years. I got the 10-gallon filter now that I’ve decided to add more fish to the tank. It works quietly and doesn’t disturb the water too much. Other than that it is durable and great value for money.
5. Whisper In-Tank Filter with BioScrubber for Aquariums
The Tetra Whisper In-Tank Filter is a powerful filter designed for 10-gallon aquariums. Its low profile design and easy to mount suction cups allow it to be mounted to the back of the tank such that it blends in with the rest of the aquarium and cleans it spotless in a matter of hours. It uses a 3 stage filtration to strain physical, chemical, and biological impurities so the water can remain fresh for a long period of time.
The filter is easy to use and all that’s needed to be done is fit it to the back of the tank and turn it on. It is self-priming therefore gets right to work as soon as it is immersed in the water. Since the water intake is at the bottom it works well even with low water levels.
- Easy to install and use
- Works with water levels as low as 2 inches
- Preassembled Bio-Bag filter cartridges that are easy to replace
- Filtration media can be customized for optimal results
- Lacks flow rate adjustment
- Unit is a bit on the heavy side
The filter is powerful and works great for my 5-gallon tank. It clears any discoloration and leftover food within minutes. If you are going to use it for low water levels, I suggest using a hook to secure it to the top of the tank as the suction cups aren’t strong enough to support the weight. It tends to fall off after a few days unless it is completely submerged in the water where its buoyancy balances the weak suction cups.