If you’re struggling to maintain good water quality in a smaller tank or aquarium, a hang on back filter (HOB filter) is an ideal filtration solution. Unlike canister filters that are often too powerful for use in smaller tanks, HOB filters provide just enough filtration performance, without intruding too much on the inside of your tank. Need to improve the water quality within a smaller aquarium? Our HOB filter buying guide has all the details you need to know when selecting a suitable filtration system for your aquarium.
HOB Filters Explained
Although HOB filters look rather large cumbersome, they are a flexible alternative to conventional cannister filters. As the name suggests, these filters are designed to be hung on the back of an aquarium. Despite being fairly large overall, the hanging nature of their design means that HOB filters do not take up much space within your tank. If you only have a small tank and require premium filtration performance, this makes HOB filters an obvious choice.
HOB filters include an extraction hose that draws water out of your aquarium, before pushing it through the external filter itself. Within this filter, several filtration stages are present which will provide effective cleaning and filtration of your tank water. Once water has been fully filtrated, it will be returned back to the main aquarium. HOB filters come in a variety of designs, ranging from modest designs that only offer limited filtration, to more advanced models that provide multi-stage chemical, mechanical and biological filtration.
One of the main benefits of HOB filters is that they are fairly easy to install. They are also easy to maintain, making them suitable for the novice with little experience with keeping fish or keeping aquariums pristine. The best HOB filters also deliver excellent flow rates, making them suitable for larger tanks with more generous capacities.
Is a HOB Filter the Right Filtration System for You?
If you want something that is easy to install and requires next to no maintenance, a HOB filter is a must. As these filters are designed to hang on the back of your aquarium, you can install one and access them without disturbing the interior of your tank. This not only makes it easy to swap our an existing filter for a HOB filter, it also ensures any future maintenance of your HOB filter can be carried out without bothering your tank and its occupants. Changing filter media cartridges and carrying out occasional cleaning and maintenance is a breeze when dealing with HOB filters.
Provided you have invested in a half-decent model, your HOB filter should also be fairly quiet. This means them suitable for use with smaller tanks, especially those placed in quiet rooms like bedrooms and home offices. A whisper-quiet filter is also less likely to cause any distress to your fish.
HOB filters are also fairly affordable. Even a first-rate HOB filter will set you back only a fraction of the cost of most canister filters and power filter options.
Choosing the Right HOB Filter
Before you choose a HOB filter, you first need to consider a few things. Most important is the size of your tank. A HOB filter will only prove effective if its power rating is sufficient for your aquarium. Ideally, you should go for a filter that is slightly more powerful than what your tank will requires. This way, any subtle changes in water conditions won’t massively impede the performance of your HOB filter. Choosing a suitably powerful HOB filter is easy. Almost every model will list what tank capacity it has been designed for use with.
Another way to determine whether or not a HOB filter is fit for task with your tank is to consider the flow rate of the device you are looking to buy. In short, flow rate refers to the volume of water that can be filtered within an hour. For best results, you should be looking to invest in a HOB filter with a flow rate at least three to four times greater than your tank capacity.
You should also think about filtration media. Some HOB filters only provide one type of filtration media, be it chemical, biological or mechanical. Other filters provide combinations of two or three filtration media. It makes sense to purchase a filter that allows you to work with all three types of media, even if you’re not actively using all of the stages. Media baskets should also be large enough for you to add or remove media at will.
Finally, you should think about maintenance. Most HOB filters are designed to be user-friendly, but some are simpler to use than others. The most important thing to focus on here is how easy the filter is to clean. Additionally, the media baskets inside should be easy to access.
Product Reviews – The Best Hang On Back Filters
Looking to upgrade your aquarium filtration system? A hang on back filter may be the perfect solution to dirty water and subpar aquarium conditions. Below are some of the best HOB filters currently available to aquarium owners.
Penn Plax Cascade Hang-on Aquarium Filter With Quad Filtration System Cleans Up to 100 Gallon Tank (CPF5),Cascade 300
The Cascade 300 from Penn-Plax is a superior choice of HOB filter for those looking to maintain a larger aquarium. This highly effective filter can deliver more than 300 gallons of water per hour, making it suitable for use with aquariums with capacities of between 55 and 100 gallons. The Quad-Filtration system makes this far more effective than other filter systems on the market. Not only does the system provide first-rate filtration, it also makes use of anaerobic bacteria to combat ammonia and nitrate build-up in your tank water. This process also enriches tank water with added oxygenation.
An activated carbon cartridge provides powerful chemical filtration, effectively getting rid of harmful toxins and invisible compounds that can be lethal to fish and marine plant life. An integrated sponge filter allows good bacteria to thrive, benefiting the biological filtration performance of this system. Finally, a poly floss cartridge is on hand to trap larger particles, preventing food and faecal debris from clouding your tank water. This system also includes a control knob that allows you to reduce filtration activity during feeding time, ensuring food particles are not removed from the aquarium before your fish have a chance to feed.
hygger Sponge Filter, Aquarium Filter Double Sponge Replaceable Media with 4 Biochemical Sponges and 1 Bag of Filtered Ceramic Balls Ultra Quiet Filter Fish Tank (S/M)
This HOB filter from Hygger has been designed to accommodate a broad range of aquarium sizes. It can be used with tanks with a capacity as little as five gallons, as well as large tanks with capacities up to 30 gallons. With three stages of filtration, you can also count on exceptionally clean water at all times, minimising the amount of time you need to spend on water testing and water changes. Mechanical filtration is provided by an effective pump action, with a sponge pad media insert easily trapping impurities within the aquarium water. This first stage should have no trouble at trapping stray food particles, fish waste and other large pieces of debris floating around in a tank.
This system also provides reliable chemical filtration. Activated carbon pellets are included in this stage of the filter, removing odours, fine particles and other elements that might cause discolouration. Finally, this system provides first-rate biological filtration. The large bio balls included here will encourage biofilm formation, ensuring helpful bacteria can thrive and help purify and oxygenate your aquarium water. This filter system is also fairly energy efficient, consuming very little voltage. What’s more, despite being very powerful, this HOB filter is fairly quiet, rarely producing noise above 40 decibels.
This FORZA hang-on-back power filter is relatively inexpensive, but is surprisingly effective at keeping your aquarium clean. This power filter is equipped with all the media required to keep on top of mechanical, chemical and biological filtration. The chamber system means you can swap out individual filtration cartridges regularly, ensuring your filter system never becomes inefficient.
Activated carbon is on hand to provide you with reliable chemical filtration, while a replaceable bio plate with a considerable surface area means that good bacteria can thrive within the filter itself. This beneficial bacteria will not only keep your water clean, but also consume harmful elements that would otherwise risk the health of your fish.
This particular filter comes in various models, with the largest size option also including a surface skimmer. This skimmer encourages better gas exchange, helping keep the surface layer of your water exceptionally clear. What’s more, this system is incredibly versatile and can be used in both saltwater and freshwater tanks. If you’re looking for a low-cost filtration option, this FORZA model is an obvious choice. You will of course have to spend money later on filter media replacements, but these are very affordable.
EA Performance Hang-On The Back Power Filter – Up to 4 Gallons – for Desktop and Betta Aquariums – NOT Made in China
If you’re looking for a powerful filter for use with a smaller aquarium, this 4-gallon system from EA is worth looking into. This filter is perfect for small tanks housing betta and nano fish, or any tank that is particularly compact. Dual-stage filtration is provided here, with both biological and mechanical performance provided. Although you’ll miss out on chemical filtration, you can compensate for this by introducing fish-friendly solutions into your tank water. Getting started with this filter is incredibly simple. Simply attach it to your aquarium, plug it in and you’re good to go.
This user-friendly filter also makes maintenance of your tank incredibly easy. The sponge media can be easily removed and replaced when required, while an adjustable flow control dial means you can turn your filter down when you need to feed your fish. The individual components are also easily detached, allowing you to carry out more in-depth cleaning or maintenance if your filter ever becomes inefficient. This 4-gallon filter is incredibly practical considering the low price, with media cartridge replacements equally affordable.
If you’re looking for a multi-stage power filter that can be hung on the back of your aquarium, this system from EA is worth considering. This high-quality filter is designed for use with medium-sized tanks and will perform well with any aquarium containing up to 30 gallons of water. You have multiple stages of filtration provided here, providing you with exceptionally clear water conditions that will help your fish thrive. The first tier, the mechanical filtration stage, makes use of poly-fibre gloss to trap organic compounds and larger pieces of debris.
If you tend to overfeed your animals, or your fish produce excessive levels of waste, this first filtration stage will help your water from becoming clouded with decaying matter. Chemical filtration is also provided here. Activated carbon media will absorb any harmful compounds that may have already dissolved in your aquarium water. This will also take eliminate toxins, unwanted odours and other agents that might be leading to water discolouration.
Finally, you have biological filtration provided. A bio sponge media insert encourages growth of fish-friendly bacteria, which will help your aquatic environments remain healthy and thrive. Media inserts come in the form of cartridges, which can be changed quickly without having to make contact with the water itself.
Installation is also straightforward, with no need to carry out excessive priming and filling prior to first use. The dual-slotted design of this filter also means you can look forward to enhanced water capacity, which ensures all levels of filtration are maximised, with a superior flow rate as standard. If other filters have proven ineffective at maintaining the water within your aquarium, this HOB system from EA is a must.
PULACO Ultra Quiet Aquarium Hang on Filter (66GPH 3W), Small Fish Tank Filter for 3 to 10 Gallons Tank
If you’ve had bad luck with noisy HOB filters in the past, this first-rate system from PULACO is something to think about. This ultra-quiet filter is one of the easiest around for fuss-free installation and general use. When activated, this system effectively removes impurities and harmful particles from aquarium water thanks to the high-grade sponge media. This hang-on filter is also one of the quietest around. Even when operating at full power with a 10-gallon tank, this filter will make very little noise. If you’re planning on setting up an aquarium in a sturdy or bedroom, the benefits of a quiet filter are obvious.
You also have an adjustable flow control dial here. You can easily increase or decrease water flow whenever the need arises. This is particularly useful for when it comes to feeding your fish, ensuring your aquatic pets can enjoy their fill before the filter pulls food particles away from the tank water. Although effective and relatively silent, this filter has some drawback. For a start, there’s only one real level of filtration provided here.
If you’re looking for effective chemical and biological filtration, you’ll need to invest in additional filters or water treatments. If you plan on using this filter as a solitary water cleaning system, you’ll definitely have to maintain a regular water treatment and changing schedule. However, this HOB filter still earns top marks for its low price and user-friendly design.
AQQA Aquarium Hang On Filter, Submersible Hanging Activated Carbon Biochemical Cotton 3 in 1 Filter Media Adjustable Water Flow with Oxygen Pump, Surface Skimmer for Turtle Betta Fish Tank 5-10 Gal
If you’re looking for a low-cost aquarium filter that provides full-level filtration, this AQQA system is something to consider. This filter combines all the functionality of a standard tank filter with the added features of a surface skimmer and aerator. Once installed, this 3-in-1 filter will ensure water is circulated at all times, with an adjustable flow meaning you can refine it to the needs of your marine plants and aquatic pets. Because of its hang-on design, this filter can house a larger style of filter plate. This makes it particularly handy for use with taller tanks and varying water heights. However, this filter is best used with tanks with a capacity of 5-10 gallons.
The multi-layered filter provides you with all the core filtration performance you’ll need. The first layer takes care of mechanical filtration, while the second boasts activated carbon for effective chemical filtration. The final layer is made from high-density cotton media that encourages fish-friendly bacteria so a healthy aquarium environment can be maintained for your fish. Although fairly affordable, you will need to regularly replace the filter media, which will come with considerable cost over time. However, this is typical of just about any filter on the market, so this 3-in-1 HOB system from AQQA is definitely worth a second look.
A hang on filter is definitely worth considering if you have a small to medium-sized tank that needs reliable water filtration. Novice aquarists will definitely benefit from using a HOB filter, with their easy installation and user-friendly design making them incredibly simple to operate and maintain.
However, if you have a slightly larger tank, you will definitely want to ensure your filter is built to accommodate a tougher workload. A high flow rate will give you a good indicator that a HOB filter can cope with more excessive water cleaning. If you want the option to tailor the filtration steps of your device, you should also think about purchasing a multi-stage filter. The best HOB filters will give you the option to make use of chemical, biological and mechanical filtration. If you opt for a three-stage system, make sure the media baskets are sufficiently large enough to house additional media and easy to access so you can carry out occasional maintenance.