Best Sponge Filters and Air Pumps for Betta, Shrimp, and Nano Tanks (2026)
Sponge filters and air pumps for betta, shrimp, fry, and nano planted tanks, paired by the makers' own tank-size ratings.
A sponge filter is a set, not a single product: the sponge, an air pump, airline tubing, and usually a check valve. Pick the sponge by the maker's rated tank size, then pick a pump rated for the same tank. For tanks up to 10 gal, the Hikari Bacto-Surge Mini or Aquatop CAF-10 pairs with the Tetra Whisper 10 or the hygger HG811 (rated 1 to 15 gal). For tanks up to 40 gal, the Hikari Bacto-Surge Small or Aquatop CAF-40 pairs with the Tetra Whisper 40. The hygger HG256 Medium covers 15 to 55 gal and adds a ceramic media chamber. Add a check valve to the airline whenever the pump sits below the water line.
Who this guide is for
This guide is for small and gentle tanks: a betta tank, a shrimp tank, a fry or grow-out tank, a quarantine tank, or a nano planted tank where a power filter feels like too much. Hikari lists nano tanks, breeding, fry-holding and quarantine tanks as uses for its Bacto-Surge sponges, and Aquatop describes its CAF sponges as suited to breeders, hatcheries, fry tanks and quarantine systems.
As a general rule, an air-driven sponge filter moves water more gently than a hang-on-back or canister filter, and its foam intake is hard for shrimp and fry to get pulled into. That gentler flow is the main reason to choose one. The trade-off is less media room and less flow across a large or densely planted tank, which our planted aquarium filter guide covers alongside other filter types. If you keep shrimp, our shrimp in planted tanks guide explains why sponge filters are often recommended for them.
Before you buy, know your tank's actual water volume. The aquarium volume calculator works it out from the tank's dimensions.
Comparison table
| Product | Fits | Best for | Skip if |
|---|---|---|---|
 Hikari Aquarium Solutions Bacto-Surge Sponge Filter (Mini)Model 96038 | up to 10 gal; low-tech tanks | A nano, shrimp or betta tank up to 10 gallons that needs gentle filtration. | Your tank is larger than 10 gallons or you do not want to run an air pump. |
 Aquatop Classic Aqua Flow Internal Sponge Filter (Up to 10 gal)Model CAF-10 | up to 10 gal; low-tech tanks | A nano, betta or fry tank up to 10 gallons, or as a pre-filter on a small filter intake. | Your tank is over 10 gallons and this would be the only filter. |
 Hikari Aquarium Solutions Bacto-Surge Sponge Filter (Small)Model 96040 | up to 40 gal; low-tech tanks | A 10 to 40 gallon community, shrimp or grow-out tank that wants a simple air-driven filter. | You need a filter for a tank over 40 gallons or want strong water movement. |
 Aquatop Classic Aqua Flow Internal Sponge Filter (Up to 40 gal)Model CAF-40 | up to 40 gal; low-tech tanks | A 20 to 40 gallon low-tech or breeding tank that wants a weighted, air-driven sponge. | You want a filter that hides behind hardscape; at 6.75 in tall it is visible in small tanks. |
 hygger Double Biochemical Sponge Filter (Medium)Model HG256 | 15–55 gal; low-tech tanks | A 15 to 55 gallon tank that wants more media than a single sponge. | Your tank is under 15 gallons; a smaller single sponge fits better. |
 hygger Mini Silent Air Pump (1.5 W)Model HG811 | up to 15 gal; low-tech tanks | A desk-size betta or shrimp tank running one small sponge filter. | You need to run more than one sponge filter or a tank over 15 gallons. |
 Tetra Whisper Aquarium Air Pump (non-UL) (Whisper 10)Model 77851 | up to 10 gal; low-tech tanks | Running a single small sponge filter in a 10 gallon or smaller tank. | You want to run two sponge filters or a tank over 10 gallons. |
 Tetra Whisper Aquarium Air Pump (non-UL) (Whisper 40)Model 77853 | up to 40 gal; low-tech tanks | Running a medium sponge filter in a 20 to 40 gallon tank. | Your tank is a nano where a smaller pump is enough. |
Every tank rating in the table comes from the maker. None of the sponge makers here publishes a flow rate, so the rated tank size is the only like-for-like way to compare them.
What makes up a sponge filter set
- The sponge. Foam on a weighted or suction-mounted base, with an uplift tube. Air bubbles rising up the tube pull water through the foam. None of the sponges below includes a pump.
- The air pump. It sits outside the tank and pushes air down the airline. Size it to the same tank volume as the sponge.
- Airline tubing. Runs from the pump to the sponge's uplift tube. The hygger HG811 comes with 3.6 ft of silicone tube. For the other pumps, check the listing for what is in the box and buy tubing if it isn't included.
- A check valve. It stops water from siphoning back down the airline into the pump when the power goes off. Hikari says back-siphoning can damage the pump or cause an electrical short. Fit it with its arrow pointing from the pump toward the tank, and check it matches your airline size.
- An air valve (optional). It lets you turn the airflow down. The hygger HG256 includes an airflow regulating valve in the box.
Sponge filters up to 10 gallons
Hikari Aquarium Solutions Bacto-Surge Sponge Filter (Mini)
- Best for
- A nano, shrimp or betta tank up to 10 gallons that needs gentle filtration.
- Skip this if
- Your tank is larger than 10 gallons or you do not want to run an air pump.
- Rated aquarium size
- Up to 10 gal
- Dimensions
- 1.77 in H x 2.17 in R
- Foam
- Polyether foam
- Drive
- Air-driven; air pump not included
- Very small footprint for nano tanks
- Polyether foam, which Hikari says gives longer life
- Needs only an air pump and airline to run
- Air pump not included
- Hikari publishes no flow rate or pore size
The Bacto-Surge Mini (item 96038) is rated for tanks up to 10 gal and measures 1.77 in high by 2.17 in in radius, so it tucks into a corner of a desktop tank. Hikari uses polyether foam, which it says gives a longer life. Hikari's page also gives setup steps worth following: soak the sponge in aquarium water for at least 5 minutes, squeeze it underwater to push out trapped air, and rinse it only in aquarium water, never tap or hot water. Hikari says the sponge needs at least 30 days to reach peak performance. It suggests replacing it every 6 months, with 2 weeks of pre-colonization before the old one comes out. Hikari doesn't publish a flow rate or pore size.
Aquatop Classic Aqua Flow Internal Sponge Filter (Up to 10 gal)
- Best for
- A nano, betta or fry tank up to 10 gallons, or as a pre-filter on a small filter intake.
- Skip this if
- Your tank is over 10 gallons and this would be the only filter.
- Rated aquarium size
- Up to 10 gal
- Pore density
- 60 pores per linear inch
- Sponge size
- 2.00 in diameter x 1.75 in tall
- Base diameter
- 2.00 in
- Total height
- 3.50 in (with sponge and uplift tube)
- Uplift tube inside diameter
- 0.56 in
- Weighted
- Yes
- Drive
- Air pump or powerhead (not included)
- Fine 60 ppi foam per Aquatop
- Weighted base stays put
- Can also serve as an intake pre-filter
- Pump or powerhead sold separately
- Small sponge suits small tanks only
The CAF-10 is Aquatop's smallest sponge, also rated for tanks up to 10 gal. Aquatop lists the foam at 60 pores per linear inch, with a 2.00 in by 1.75 in sponge, a weighted 2.00 in base, and a total height of 3.50 in including the uplift tube. The uplift tube's inside diameter is 0.56 in. It runs on an air pump or a powerhead, neither of which is included. Aquatop also says it can serve as a pre-filter on most external or top filters, which is useful if you want to cover a small power filter's intake in a shrimp or fry tank.
Sponge filters up to 40 gallons and beyond
Hikari Aquarium Solutions Bacto-Surge Sponge Filter (Small)
- Best for
- A 10 to 40 gallon community, shrimp or grow-out tank that wants a simple air-driven filter.
- Skip this if
- You need a filter for a tank over 40 gallons or want strong water movement.
- Rated aquarium size
- Up to 40 gal
- Dimensions
- 2 in H x 4.75 in D
- Foam
- Polyether foam
- Drive
- Air-driven; air pump not included
- Covers tanks up to 40 gallons per Hikari
- Polyether foam for longer life per Hikari
- Simple air-driven design with no impeller
- Air pump not included
- Hikari publishes no flow rate or pore size
Despite its name, the Bacto-Surge Small (item 96040) is rated for tanks up to 40 gal. It measures 2 in high by 4.75 in across and uses the same polyether foam and setup routine as the Mini. Hikari also makes Large (up to 75 gal) and X-Large (up to 125 gal) sizes, which aren't covered here. As with the Mini, Hikari publishes no flow rate.
Aquatop Classic Aqua Flow Internal Sponge Filter (Up to 40 gal)
- Best for
- A 20 to 40 gallon low-tech or breeding tank that wants a weighted, air-driven sponge.
- Skip this if
- You want a filter that hides behind hardscape; at 6.75 in tall it is visible in small tanks.
- Rated aquarium size
- Up to 40 gal
- Pore density
- 40 pores per linear inch
- Sponge size
- 5.00 in diameter x 3.50 in tall
- Base diameter
- 3.25 in
- Total height
- 6.75 in (with tube)
- Uplift tube inside diameter
- 0.75 in
- Weighted
- Yes
- Drive
- Air pump or powerhead (not included)
- Larger 5 in sponge than the CAF-10
- Weighted base
- Works with an air pump or a powerhead
- Pump or powerhead sold separately
- Coarser 40 ppi foam than the CAF-10
The CAF-40 is rated for tanks up to 40 gal. Its sponge is 5.00 in across and 3.50 in tall on a weighted 3.25 in base, and the whole filter stands 6.75 in tall with the tube. That height is visible in a small tank, so plan where it goes before you scape. The foam is coarser than the CAF-10's at 40 pores per linear inch, and the uplift tube is wider at 0.75 in. Aquatop states it suits freshwater and saltwater.
hygger Double Biochemical Sponge Filter (Medium)
- Best for
- A 15 to 55 gallon tank that wants more media than a single sponge.
- Skip this if
- Your tank is under 15 gallons; a smaller single sponge fits better.
- Rated aquarium size
- 15-55 gal (Medium)
- Size
- 6.3 x 9 x 14 in (Medium, as listed by hygger)
- Media
- Sponges plus bio-ceramic balls in a media container; 2 spare sponges included
- Mounting
- 2 suction cups or hang-on extendable clip
- Outlet
- Adjustable 360-degree outlet
- Included
- Retractable outlet pipe with air tube connection, double sponge filter with media container, ceramic pearls, 2 suction cups, 2 replacement sponges, airflow regulating valve, filter support, manual
- Drive
- Air pump required (not included)
- Sponges plus a ceramic media chamber
- Two mounting options
- Spare sponges and an air valve in the box
- Air pump sold separately
- Tall body is hard to hide in small tanks
The HG256 Medium is rated for 15 to 55 gal and measures 6.3 x 9 x 14 in as hygger lists it. It's the only filter here with a media container: two sponges plus bio-ceramic balls. The box includes two spare sponges, an airflow regulating valve, a filter support, and two suction cups, and you can mount it with the suction cups or a hang-on extendable clip. The outlet rotates 360 degrees. hygger advises cleaning the sponges in aquarium water every 2 to 4 weeks. hygger also sells a Small size rated for 10 to 40 gal. At 14 in tall it isn't easy to hide in a short tank.
Air pumps
hygger Mini Silent Air Pump (1.5 W)
- Best for
- A desk-size betta or shrimp tank running one small sponge filter.
- Skip this if
- You need to run more than one sponge filter or a tank over 15 gallons.
- Rated aquarium size
- 1-15 gal
- Power
- 1.5 W
- Airflow
- 420 mL/min
- Drive
- Piezoelectric ceramic plate (no motor)
- Included
- Air pump with power adapter, 0.9 in air stone, 3.6 ft silicone tube, double-sided sucker, manual
- Motorless piezo design, which hygger says is very quiet
- 1.5 W power draw
- Tubing and air stone included
- Low output; suits one small sponge only
- No check valve listed in the box
The HG811 uses a piezoelectric ceramic plate rather than a motor, which hygger says makes it very quiet. It draws 1.5 W and hygger lists 420 mL/min of airflow. The box includes a power adapter, a 0.9 in air stone, 3.6 ft of silicone tube, and a double-sided sucker. hygger rates it for 1 to 15 gal tanks. hygger says the pump isn't submersible and should sit above the tank's water level. If it can't, hygger says to install a check valve to prevent backflow, and none is listed in the box.
Tetra Whisper Aquarium Air Pump (non-UL) (Whisper 10)
- Best for
- Running a single small sponge filter in a 10 gallon or smaller tank.
- Skip this if
- You want to run two sponge filters or a tank over 10 gallons.
- Rated aquarium size
- 10 gal
- Airflow
- 0.5 L/min
- Small pump sized for one nano sponge filter
- Established brand
- Lowest airflow in the Whisper line
- Non-UL version
- Tetra's pages do not list a check valve as included
The Whisper 10 (item 77851) is the smallest pump in Tetra's Whisper line, which Tetra rates for aquariums from 10 to 100 gal. This non-UL version is rated for 10 gal. Tetra's non-UL page lists only the tank size. The 0.5 L/min airflow shown on the card comes from Tetra's page for the UL version of the Whisper, so treat it as a guide rather than a confirmed spec for this exact pump. Tetra's pages don't list a check valve as included.
Tetra Whisper Aquarium Air Pump (non-UL) (Whisper 40)
- Best for
- Running a medium sponge filter in a 20 to 40 gallon tank.
- Skip this if
- Your tank is a nano where a smaller pump is enough.
- Rated aquarium size
- 40 gal
- Airflow
- 1.3 L/min
- More airflow than the Whisper 10 for larger sponges
- Established brand
- Non-UL version
- Tetra does not list the outlet count on the pages fetched
The Whisper 40 (item 77853, taken from the Amazon listing) is rated for 40 gal. Its 1.3 L/min airflow also comes from the UL version's page, not the non-UL page. Tetra's pages don't state how many outlets it has, so don't count on running two sponges from it without checking. For a tank above 40 gal, Tetra's line continues with the Whisper 60 and Whisper 100, which aren't covered here.
How to choose
Match the pump to the sponge by tank rating
None of these makers publishes a chart pairing a specific pump with a specific sponge, so the simplest approach is to use the tank ratings both makers give. Choose a sponge rated for your tank, then a pump rated for the same tank size or a little larger:
| Tank size | Sponge options | Pump options |
|---|---|---|
| Up to 10 gal | Hikari Bacto-Surge Mini, Aquatop CAF-10 | Tetra Whisper 10, hygger HG811 (1 to 15 gal) |
| 10 to 15 gal | Hikari Bacto-Surge Small, Aquatop CAF-40 | hygger HG811, Tetra Whisper 40 |
| 15 to 40 gal | Hikari Bacto-Surge Small, Aquatop CAF-40, hygger HG256 Medium | Tetra Whisper 40 |
| 40 to 55 gal | hygger HG256 Medium | A pump rated above 40 gal |
A pump rated for a larger tank than the sponge can push more air than you want, which means more bubbles and more surface movement. A small air valve, like the one included with the HG256, lets you turn it down. If a pump seems too weak to drive a sponge well, the usual fix is a larger pump rather than a valve.
Betta, shrimp, fry, and nano tanks
- Betta tanks. Bettas generally do better in calm water. A sponge sized for the tank, with airflow kept moderate, is a common choice.
- Shrimp and fry. The foam itself works as an intake guard. The CAF-10 can also go on a small power filter's intake as a pre-filter.
- Nano planted tanks. Pick the smallest sponge that fits the tank rating, and place it where plants or hardscape partly screen it. Our nano planted tank setup guide covers equipment layout.
CO2 and surface movement
We list these sponges for low-tech tanks. Rising bubbles break the surface, and surface movement drives off dissolved CO2. In a CO2-injected tank that's usually a reason to choose a different filter, or at least keep the airflow low.
Compatibility
- Air supply: every sponge here needs an air pump. The Aquatop CAF models can also run on a powerhead.
- Freshwater and saltwater: Hikari, Aquatop (CAF-40) and hygger (HG256) state their sponges suit both.
- Mounting: the Aquatop CAF models have weighted bases. The HG256 uses suction cups or a hang-on clip.
- Power: the HG811 is the only pump here with a published power draw (1.5 W).
Maintenance
Rinse the sponge in a bucket of old tank water during a water change, never under the tap. Hikari and hygger both say to use aquarium water, and hygger suggests every 2 to 4 weeks for the HG256. Our maintenance checklist helps fit this into your routine.
Alternatives and when to skip buying
If your tank already has a hang-on-back or canister filter that keeps the water clear, a sponge filter isn't required. For shrimp or fry, a CAF-10 used as a pre-filter on the existing filter's intake may be all you need. For a larger, densely planted or CO2-injected tank, a canister usually suits better. Our canister filter picks sort those by rated tank size. And if you already own a spare air pump rated for your tank, you only need the sponge and a check valve.
How we chose
We matched each product to its Amazon listing by brand, model and size, and took specifications from Hikari, Aquatop, hygger and Tetra product pages. Where a listing and a maker disagreed, we used the maker's figure. The Tetra airflow figures come from Tetra's UL-version page, which we note on each pick. Compatibility came first: rated tank volume, the air supply each sponge needs, and how pump and sponge pair up. We only included products with strong buyer feedback when we checked. We haven't tested these products hands-on, and we don't rank or score them.
Related guidance
- Planted aquarium filter guide
- Shrimp in planted tanks
- Nano planted tank setup
- Canister filters for planted tanks, for larger tanks that need more flow and media
- Care and maintenance topics
- Planted betta tank guide, for gentle flow in a betta tank, and sponge filter vs canister filter if you're still choosing a filter type
Sources
- Bacto-Surge Biological Action Sponge Filters, Hikari
- Internal Sponge Filter CAF-10, Aquatop
- Internal Sponge Filter CAF-40, Aquatop
- CAF Sponge Filters, Aquatop
- Aquarium Double Biochemical Sponge Filter (HG256), hygger
- Aquarium Mini Silent Air Pump with Accessories (HG811), hygger
- Whisper Aquarium Air Pump (non-UL), Tetra
- Whisper Aquarium Air Pump, Tetra
- Aquarium Solutions Check Valve, Hikari
This page is research-based: we have not tested the equipment or methods ourselves. It draws on the sources listed and established hobby practice.
Keep reading
Choosing a Filter for a Planted Aquarium
How canister, hang-on-back, sponge, and internal filters suit planted tanks, how to size flow realistically, and how to maintain media without harming the cycle.
Keeping Shrimp in Planted Tanks
How to keep Neocaridina and Caridina dwarf shrimp with live plants: water parameters, copper risk, aquasoil, filter safety, acclimation, and fertilizer cautions.
How to Set Up a Planted Nano Tank
How to set up a planted nano tank of roughly 2 to 10 gallons: scaled-down equipment, small plants, suitable livestock, and a steady maintenance routine.