Sponge filters get a bad rap sometimes. They’re considered inferior, but in the right tank, you’ll quickly find that they’re an excellent addition to your equipment. They’re not super complicated, but there are still some big differences in them.
Read on, and I’ll show you how to decide if a sponge filter is right for your tank, and how to end up with the best!
Best Sponge Filters
1. Aquapapa Bio Sponge Filter-Best Overall Sponge Filter
Sometimes simple is best, and I find it hard to recommend anything better for the average small tank. The design is simple, just a sponge and port for the airline, which allows you to hook it up easily.
This particular model comes in a pack of three and suggests that they can handle up to 55 gallons. That may be a bit overstated, but adequate airflow should allow them to handle up to 30 gallons as a primary filter.
They’re cheap enough that even picking up a pack for one tank isn’t a bad idea. While sponge filters often last for a long time, a couple of bits of extra equipment is never a bad thing.
The downside? They’re a bit big for nano-tanks. I’d recommend grabbing something smaller for anything under 10 gallons.
That’s the only real drawback to this simple design, however. Once you’ve hooked it up, it’ll do its thing until it falls apart, which makes it the top choice on our list.
- Simple design
- No mess startup
- Comes in a three-pack
- A bit large for tanks under 10 gallons
- No bioreactor
2. Hygger Aquarium Double Sponge Filter-Best for Large Tanks
The double-sponge Hygger Aquarium filter is a great bet for larger tanks. The dual-sponge design actually draws a decent current for a sponge filter, and the bioreactor in the bottom portion of the “towers” adds to its value.
These are relatively large filters, much more suitable for tanks in the 20 gallons to 40 gallons range than smaller tanks.
My favorite part is that they can be positioned to avoid the problems with bubbles created by some sponge filters. The output of the filter is at the top of the unit and can be placed above the water level in the tank. When doing so, it’ll create a small, quiet stream of water without too much disruption across the tank.
It’s a little bit expensive, and they’re large as we said before. It also needs a bit more power than many on our list. However, the overall quality is good, and it’s in the top tiers of the technology when it comes to features.
If you have a larger tank and want a sponge filter, I recommend looking no further. It’s a great buy and has enough features to make it stand out as more than just a “big sponge filter.”
- Outflow can be positioned above water level
- Great for tanks over 20 gallons
- Tight sponges for extra surface area
- Needs at least a 4W air pump, 8W+ is better
3. UPETTOOLS Aquarium Biochemical Sponge Filter-Best Sponge Filter for Nano Tanks
If you’re looking for a sponge filter for a ten-gallon tank, or even smaller, then look no further. This one has an advanced design while remaining small enough to fit in any of the common nano-tank sizes.
This one is particularly well suited for tanks in the 2.5 gallon to 5-gallon range, but it’s usable up to 10 gallons. It features a relatively tall sponge and a small bioreactor chamber underneath it, putting it as one of the more advanced designs.
You’ll also be able to control the filter’s output, the head moves in a full circle and can be placed above the waterline to avoid water agitation if you so choose.
The only real drawback is the small size of the filter. The sponge will also clog more easily than some owing to its tight pores, but that’s not much trouble at all if you stay up on maintenance.
If you’re looking for a sponge filter that’s perfect for a small tank, this is the perfect option. Sometimes it pays off to go beyond the basics, and the price jump is smaller than you’d think to get a great filter instead of just a good one.
- Perfect for small tanks
- Excellent bioreactor
- Controllable output
- Small size makes for easy concealment
- Requires frequent maintenance
- Very small size
4. Huijukon Double Super Biochemical Sponge Filter-Best Double Filter
If you’re a fan of simple but don’t feel like running multiple air lines? This is what you’re looking for. It’s a larger setup with two sponge towers, and it works remarkably well in medium-sized tanks.
This is another of the sponge filters with remarkably tight sponges. That’s good for keeping bacteria, but it also means that they’ll clog easier. It’s a bit of a trade-off but nothing to worry about in the majority of tanks.
When we reviewed them, they were quite cheap as well. I don’t recommend the “full package” deal; however, the cheap air pump is quite loud and obnoxious. Skip it and use a good one.
As a double filter, it also requires a bit more air than many. It also needs an airstone. It has a tendency to release some serious bubbles if you don’t. It also doesn’t have a bio-reactor, which can turn some people off.
For aeration and cleaning in a mid-sized tank? This one ranks high on the list. Just be aware it’s a bit big, and the brand doesn’t hold up when it comes to the air pump. The filter itself is rock-solid and dirt cheap, however.
- Double stack of sponge filters
- Great for tanks 20 to 50 gallons
- High-quality sponges
- Easy to adjust the output
- Air pump included in the package deal is terrible
- Needs an airstone to avoid overly large bubbles
5. QANVEE Fluidized Moving Bed Filter-Advanced Sponge Filter
Looking for something a bit more extreme than the majority of sponge filters? This might be the right option. With the ability to handle up to 40 gallons of filtration, this isn’t a bad choice for anyone, but it stands out in the relatively dull world of sponge filters.
The difference here is that this one has an exceptionally large bio-reactor. The sponge is a thin disk which sits at the bottom of the tube, while the reactor above moves the ceramic media around.
Theoretically, this is something of a bacterial Thunderdome. The older bacteria get knocked off the ceramics as they collide, and newer, stronger bacteria adhere to it. I’m not sure that the claim is valid, but it does mean that minimal cleaning is required.
The downside? They’re a bit expensive for a sponge filter and the smaller sponge may clog quickly.
On the other hand, it’s a step forward in air-powered aquarium filters and it does the job it was created for. It’s a combination of high-tech and old school that may be a step forward from simpler sponge filters.
- Eye-catching design
- Simple to use
- Works for larger tanks
- Expensive for a sponge filter
- Thin sponge requires extra maintenance
Picking Your Sponge Filter
The simplicity of sponge filters makes them an easy pick for those who are looking to find the right one.
Sizing is the most important part of the equation. I recommend running at least 150% capacity if your sole filtration source is sponge filters. The sponge allows bacteria build-up, and a larger sponge means more microfauna available to keep your water clean.
Quality can be an issue with sponge filters, but it’s rare. Most of them will last for years. The truth is that there are no moving parts in most, so there’s not a lot to skimp on. The only problem which can occur is sponges that break down more quickly.
The main decision for most people is which extra features you’re willing to pay for. If you’re using it as a supplement to a canister or HOB filter, then you should be fine with a plain sponge filter.
On the other hand, many people use them as the sole filtration source. If that’s the case, look for a ceramic media reactor. The porous material allows bacteria to gather in enormous quantities compared to the space available, which helps keep water chemistry stable.
Lastly: consider the size of the filter. Large filters are harder to hide, while smaller ones can easily be slipped behind hardscape elements to preserve your aquascape. A shrimp breeder may not care, for instance, but you don’t want an enormous bubbling monster in the display tank in your living room, either.
The overall construction can lend itself to harder or easier attachments for the airline that comes in, but should only be a serious consideration if you’re trying to pull off a completely hidden filter in a tight spot.
So, ask yourself the following:
- Does this sponge filter work for my tank’s size?
- Can I hide the filter where I’d like?
- Do I want the extra surface space for microbes?
That’ll be enough information to help you find an excellent sponge filter for your tank. You’ll need one more purchase to use them, however.
Recommended Air Pumps for Sponge Filters
Sponge filters work by having bubbles pumped through them. This creates suction and pulls water through the sponge. The sponge itself catches larger debris, while the surface inside hosts microorganisms that balance the water.
Air pumps are easy to find and cheap. The problem is that many of them generate a lot of noise and vibration, so it’s important to find a good one.
If you’re not super sensitive to sound, I recommend picking up an appropriately sized Tetra Whisper to power your sponge filter.
One thing to note: you’ll need at least 10GPH and possibly more depending on tank depth to run a double-armed sponge filter.
You may also need a larger pump than your tank is rated for if you have an exceptionally deep tank for the tank’s volume. Deeper tanks have more backpressure, so the output might not be sufficient in extreme cases.
Sponge Filter FAQ
Is a Sponge Filter Right for My Tank?
As a primary filter, sponge filters are somewhat lacking. Nano-tanks, tanks housing Betta, and shrimp tanks are good examples of places where a sponge filter works as a primary filter. For secondary filtration, they’re an excellent option, and a clever setup can serve a lightly stocked tank up to 60 gallons as a primary filter.
How Do I Clean My Sponge Filter?
It’s best to shake out the detritus and other organic bits every couple of weeks. If the sponge filter is your primary filter and you don’t have a reactor, then you should only clear half of the sponge at a time. This helps keep beneficial bacteria in the system.
What Can I Do if My Sponge Filter’s Bubbles Are Too Big?
In some systems, particularly shallow tanks of ten gallons or less, the disturbance created by bubbles at the surface is a major problem. Use an airstone instead of plugging the air line directly into the sponge to help the problem. The same amount of flow will be present, but the bubbles will diffuse in a more controlled manner.
Are There Any Installation Precautions for Setting Up a Sponge Filter?
Like any piece of aquarium equipment, a drip line is required for the air pump’s plug-in. That means allowing the wire to go all the way to the ground before plugging it in. A check valve should be on the air line for any pump lower than the tank. Otherwise, backpressure can fill the tubing and allow water into the air pump when it’s turned off.
Are Sponge Filters Safe for Small Fish?
The main reason breeders use them is due to safety. Even the smallest fry or shrimplet can’t be sucked into a sponge filter. The gentle flow also means they won’t be stuck to its surface. They’re optimal for any fragile animals you’re trying to keep in an aquarium.
Does the Sponge in a Filter Wear Out?
In real terms? Sure, eventually, the sponge will decay. Practically, they have a relatively unlimited lifespan, which also keeps you from having to replace the filter. The bio media in reactors will also last until it crumbles. To be fair, there’s nothing special there, just ceramic with a lot of surface area by virtue of its pores.
How Large of a Tank Can Be Cleaned by a Sponge Filter?
In my opinion, anything over 40 gallons is pushing it. At that point, you’ll have to run three or four sponge filters, a high powered air pump, and generally do a lot of work. You may as well go with a hang-on-back or canister filter at that point, the only advantage of the sponge is that it’s cheaper. That said, large tanks with minimal bioload(i.e., shrimp breeding tanks) are good candidates since they minimize maintenance.
Can I Use My Sponge Filter as a Prefilter?
Some people use sponge filters to remove large particles before they go into the main filter. In most cases, it’s better to buy a separate sponge and stick it over the HOB or canister filter’s intake. There are specialty sponges available for just this purpose.
Are Sponge Filters Good at Keeping Water Clear?
If you’re not running a filter? Absolutely. They can also increase water clarity when running as a secondary filter. Unfortunately, if crystal clear water at all times is what you’re looking for, then you’ll want to use a canister or HOB filter. The sponge will catch some debris, but the main benefit is biological.
Why is My Sponge Filter Not Working?
Check to make sure that all of your air line connections are tight. As long as that’s the case, then you should look at the seals on the filter itself. Any connections which are broken will have bubbles leaking out. If there’s only a light drizzle of bubbles (or none at all), then your air pump is too weak for the depth the filter’s been placed at. You can raise the filter if it has suction cups, or you can replace the air pump with a higher-powered model.
Bubble Debris Away
Sponge filters are simple devices, but they can be game-changers depending on your aquarium setup. A good one is simple, dependable, and cheap. For the most part, the design has been perfected these days, but you never know what exciting advances might emerge over time. For now? Pick one of the above that suits your tank, and you’re in good hands!