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What’s The BEST TYPE Of Aquarium Filter? Fish Tank Filter Basics!

By KG Tropicals on

Male Speaker: Whether you're setting up your first fish tank or your 30th, you're going to need some type of filtration in there to keep the water moving and keep it clean. Choosing a filter can be an intimidating thing because there's so many different types and a whole bunch of brands, but which one is best for you? Well, that's what this video is all about. We're going to be talking about what aquarium filters do, the different types, how to install them, and how to maintain them. Basically, everything you need to know about aquarium filters. Let's get started.


If you ask someone that's brand new to fishkeeping what an aquarium filter does, they'll probably say something like, "Well, they clean the water, duh." Well, this is true, but they do so much more than that. An aquarium filter not only cleans the water, but it also serves as a breeding ground for beneficial bacteria and keeps the water moving. If you heard me say breeding ground for beneficial bacteria and you're totally confused about what that is, I'll put a card to a video up here that I did about that. Definitely go watch that, it'll make everything makes so much more sense. It's literally a must-watch for new fishkeepers.

Water movement is the other critical function of a filter and this is one of the most important factors to keeping a healthy aquarium. Here's what I'm talking about. Think about the way a fish breathe, how they're able to breathe underwater. They do this by taking water in through their mouth and then their gills pick up dissolved oxygen and then expel carbon dioxide.

Obviously, oxygen doesn't just magically appear in the water. It enters the water from the surface, but carbon dioxide is also released through the surface of the water. This is what you'll hear fishkeepers referred to as gas exchange. It's basically the water breathing. It's taking in oxygen and sending out carbon dioxide. The problem is this is a process that's drastically slowing down stagnant water. If the water is just sitting there, there's nothing to speed up the gas exchange. There's very little oxygen coming in and very little carbon dioxide going out.

This is why when the power goes out and there's no more water movement in your aquarium, you'll see your fish go up to the top like they're gasping for air, while they're trying to go where the oxygen is. It's like a garage with a running car and it builds up carbon dioxide and whoever's in there eventually suffocates. This is the same thing happening in your aquarium. How do you remedy that? By opening the garage door.

Having water movement in the aquarium is not only like opening the garage door, it's more like opening the garage door and then sticking a fan there to constantly be drawing in the fresh air and pushing stale air out. Anyway, this is my long-winded way of saying that filters are not only important for growing bacteria and catching debris, but they also provide water movement which is vital to your aquarium's health. All right, now that we've got that over with, let's talk about the different things types of filters and Lisa is going to start off with the simplest of all filters and that sponge filters.


Lisa: Sponge filters are without a doubt the easiest filter to use in your aquarium. They're super easy to set up and they don't have any moving parts and they're a lot more efficient than you might think. The way they work is you connect an air hose to a fitting inside the sponge and then hook the other end to an air pump. The pump creates bubbles which naturally want to travel up. When they travel up through the tube, it creates a current which draws water through the sponge catching loose debris.

As simple as this concept is you probably think it wouldn't be all that efficient, but you'd be wrong. They're incredibly efficient because it checks every box for a filter. You have the sponge that catches debris just like any other filter plus sponges are a great place for growing beneficial bacteria and you've got water movement from bubbles. It's perfect. Maintaining a sponge filter is super easy. All you need to do is fill up a bucket with the water from your aquarium, the existing water, and put the sponge in there, squeeze it out, and then just stick it right back in the tank. It's that easy.

Sponge filters may not be the most attractive choice of filters, but they're super easy to install, a breeze to maintain, and incredibly efficient. If you're worried about power outages, if you have a battery or a USB air pump, then it's no problem at all. When the power goes out, just hook up that backup pump to your sponge filter and just go on with your business. It couldn't be any easier.


Male Speaker: Hang on the back filters are by far the most common filter in the aquarium hobby and that's for good reason. Everything about them is easy. From installation to maintenance and efficiency, these filters check every box. Hang on the back filters are exactly as they sound. They're a box-type filter that installs on the top edge of your aquarium. They draw water in through the intake and bring it back to the box where it's processed by the media and then sent back out into the tank.

Most of these filters are designed to be easy to install and easy to maintain because the media comes in either the form of a disposable cartridge or simple trays that can be lifted out. Installing them is usually just a matter of hanging the box on the tank, inserting the intake tube, placing the trays or cartridge in, and then plugging it in. That's it. Hang on the back filters are definitely a step up from sponge filters because with that box back there, it allows you to start adding things like ceramic discs and bio balls and stuff like that, different types of bio media. Plus most of them will also contain activated carbon which is just another thing to help keep the water crisp and clean and not smelly.

I know there's going to be some people that are going to say, "Activated carbon is bad." Come on, cut us a break here. People have been using carbon in aquariums for longer than your grandfather has been alive. Maintaining a hang on the back filter is ridiculously easy. Most of them are as simple as removing the cartridge and installing a new fresh one. You can also remove the box from your aquarium and dump it out to get all that nasty stuff out of there, but I do want to caution you about something.

There's a lot of life in your filter that is vital to your aquarium's health. You don't want to wash all of that away. If you see a huge buildup in your filter, just dump it out, don't scrub it down. I understand why you might want to but just trust me on this one, just leave it alone. They're easy to install, easy to maintain and very efficient. Are they perfect? Well, no. They certainly have their flaws.

The first is some of them can be a little noisy. I've been a fishkeeper for a long time. There's one thing that I have hated since day one. That's a noisy fish tank. I don't want vibrations, I don't want humming from pumps, and I don't even like the sound of water movement or bubbles. In a pond or a water feature, yes, that's fine, but in my living room or in my office, no.

The only other complaint I have is I'm not the biggest fan of disposable cartridges. For the new fishkeeper, they are great, but for me, I like more options. On that note, if you want to talk about options, we got to talk about canister filters.


Lisa: When you're ready to take your filter game up a level and get an advanced filtration system, one of your first options is going to be a canister filter. These are filters that are usually used on larger tanks because they process a ton of water very efficiently. Canisters are going to install on a cabinet below your aquarium, they'll have an intake hose that usually will mount on the back wall of your tank, and it runs down to the canister where it's processed through the sponges and media, then sent back through the return hose in your tank.

It's similar to hang on back filters, but has long hoses connecting to it rather than the filter just mounting right on the tank. The biggest benefits to canisters is they have a ton of room in them to install a variety of sponges and media, and it usually holds way more of it than hang on the backs do. Plus with the large capacity and more powerful motors, canisters will filter the water more than smaller hang on backs. More water in, more water out.

Installing canister filters is much more technical than sponge filters are hanging on the backs but you don't have to be an engineer. Just follow the instructions and take your time. One of the trickiest things you've got to do with canisters, it's some of them come with one long piece of hose which you have to cut to the right sides. Take your time with this because you've only got one shot at it. Cut it too short and you've ruined it. [unintelligible 00:08:53] the hose a little bit longer than needed is always going to be better than it not being long enough.

The pros and cons to canisters. Let's start with the pros. The first one should be pretty obvious. As I said earlier canisters have a ton of space in them so you've got tons of options as to the type of media you can install in there. The second pro is they're super quiet. Most of them are pretty much silent which makes that man of mine very happy. The last pro is since you don't have the big box mounted on the back of your aquarium, you can put it closer to the wall. This might not be a big deal for everyone, but if your aquarium is in a small room, every single inch helps.

Of course, there's plenty more pros to canisters, but that's just a few. Let's move on to the cons. The first con is they're a lot more difficult to install and maintain. Again, this isn't rocket science, but if you're looking for something super easy, canisters might not be the right choice for you. The next con is cost. Canister filters are stupid expensive. Most of them are going to be well over $100 which is like triple the cost of hang on the back filters and 10 times as much as a sponge filter. When it comes to maintenance, it's not the worst thing in the world, but it's much more difficult than the others because you've got to disconnect the hoses and remove the filter from under the tank.

Some of them are pretty heavy. It's also pretty much impossible to get inside canisters without getting water everywhere. I'd recommend taking the filter outside before you open it up, or if you have a smaller model at least put it in your sink or bathtub. Overall, canisters do a great job of processing a lot of water and doing it very quietly. They just cost more and can be a pain in the butt to maintain.

If that doesn't scare you then you definitely can't go wrong with a canister. We have like six or seven, I think, on our tanks and John, he just loves them.


Male Speaker: It's time to get serious. It's time to talk about the most advanced filtration system in all of the aquarium hobby. It's time to talk about sumps. Sumps are the most versatile filtration system in the hobby. You can literally do anything you want with them. Here' the concept of a sump. It's another filtration that will be installed under your aquarium and it'll be hooked up to the aquarium with drain hoses in a return. The water is fed through the drain by gravity. Once it gets to the tank, it usually goes through a series of different compartments where it'll flow through filter socks, sponges and bio media before being sent back to the aquarium through pumps.

There's two different approaches when it comes to sumps. The first is the manufactured kind, the ones that are built for you and you just install them. I have those in both of these tanks back here. The other is something that a lot of people have a lot of fun with and that's making your own sump. Regardless of whether you buy one pre-made or you DIY your sump, your options are practically endless with what you can do with them. For our sumps, we have a filter sock, then the water flows through a series of trays full of bio-media and chemical media, then it flows into the main sump which has our heaters in it and the pumps that send the water back up to the tank.

Then there's the reserve tank. This is a tub full of water that the sump will pull from when the water evaporates, which is nice because I don't have to constantly top off the water between maintenance. Honestly, there's so many things I could do with these two sumps that I have in these tanks, but they're working great as is. I'm a firm believer in if it ain't broke don't fix it. When it comes to pros and cons for sumps, the biggest pros are going to be the versatility and efficiency. These systems process a ton of water and the options are endless with what you can do with them. I know this one is minor but another pro for some systems is you can get your heaters out of your tank and get them hidden down below. It's nice.

For the cons, well, these can be pretty tricky to set up. There's definitely more potential for leaks. When you consider all the materials needed to get one going whether you're buying a pre-made unit or set up one yourself, it's going to cost a pretty significant amount of money. Then there's my biggest problem with sumps and that is that they are noisy. I've already talked about it, I don't like noise in my fish room and I've never found a quiet sump. It's not like they sound like you're in a factory or something but for me, my fish room is also my office. I need it to be super quiet. Let me turn the music off and let you listen to my sumps.


These are high-end, very efficient sumps. I'm actually considering using multiple canister filters on these tanks whenever I finally move them down into the basement, not because I think canisters are better than sumps. I'd do it specifically to keep the noise down. Sumps are amazing. They're probably the most efficient way of filtering an aquarium, the most advanced, the most versatile, the most options, everything is just next-level when it comes to sumps.

They can be pretty tricky. If you're not into all that stuff, if you're not good with DIY, if you're not good with problem-solving, this might be a filtration system that you want to stay away from, at least in the beginning.


Lisa: There's a couple other filters in the hobby that do a great job but we didn't want to spend a lot of time on them because you just don't see them as much anymore. Let's just go through on real quick. The first is internal box filters like these that we have in our King betta tanks. These are basically hang on the back filters in reverse. Instead of the filter mounting on the outside of the tank, it's mounted on the inside. These filters do a great job filtering the water but they take up quite a bit of room. If you're installing it into a smaller nano tank, you might not want to sacrifice that valuable space.

Next is under gravel filters. These filters went out of style a long time ago but you can still see some of them out there. The concept is there's a tray installed under your substrate with tubes extending up the back corners. You install powerheads or an airline to the top of those tubes which draws water up the tube. With water drawn up through the tube, it naturally pulls water down to that tray trapping all of the debris on the bottom of the tank.

Under gravel filters work but they can get clogged up pretty easy depending on what kind of substrate you use. Sometimes they can be a little bit harder to maintain. You'd probably be best to just avoid them especially if you're a new fishkeeper.


Male Speaker: The filter on your aquarium is the most critical piece of equipment to ensure you're providing a healthy environment for your pets. You're going to want to pick a filter that's easy to install, easy to maintain and does a good job keeping your aquarium clean and healthy. As you've seen in this video, you have several options when it comes to selecting your filter.

My advice to you is take your time making this decision. Think about what's going to be involved in maintaining it, think about how it's going to look in your tank, think about the effect it's going to have on the ambiance in the room. Is it going to be noisy and drive you crazy like me? Or is it going to do a great job and it's so quiet you don't even realize it's on? These are all things that will make or break this hobby for you and we want to help keep you in this hobby.

I hope this video has helped you out in making this pretty difficult decision. If it did and you'd like to see more videos like this, you can click right here to subscribe to the channel and make sure you click the notification bell right next to the Subscribe button so that you get notified whenever we put up a new video like this. If you want to see the last video we did in this series, you can click right here. If you want to see a video that YouTube thinks you'd like to watch, you can click right here. Thank you so much for watching and, hey, let's all do our part to help keep fishkeepers fishkeeping.

About KG Tropicals

There are many aspects to keeping an aquarium. Many newcomers to the hobby can be quickly overwhelmed. The KGTropicals YouTube channel was created to be a place for no nonsense information about the hobby, a place where the information is delivered in a way that even the most inexperienced fish keeper could understand. Whether you want to breed aquarium fish, heal a sick or injured fish or you just want to know how to set up your first tank, KGTropicals has you covered.

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