The 4 Best Filters for Axolotls of 2023

A filter for axolotls we recommend on a blue background — The Spruce Pets / Amelia Manley

Filters for your axolotl tank are necessary to keep your pet healthy by removing waste and providing good bacteria that break down harmful waste chemicals. Because axolotls absorb water and oxygen through their skin, they are especially sensitive topoor water quality, making the right filteressential to their health.

“Axolotls produce waste in the form of ammonia that dissolves in the water,” said Laurie Hess, DVM, exotic animal veterinarian atChewy. “As they suck water in while breathing and feeding, they are exposed to these toxic waste products. Filters mechanically remove large waste particles and provide good bacteria that break down ammonia into less harmful chemicals.”

Not just any aquarium filter is appropriate for axolotls. Avoid in particular substrate filters—also known as under-gravel filters—which are installed inside the tank and often cover the entire bottom, beneath your substrate. Substrate filters pull water through the filter from below the substrate (typically sand or gravel) and return clean water to the top of the tank. However, this mechanism of filtration tends to disturb the material at the bottom of your tank, which can be dangerous for an axolotl.

“This sort of filter is not recommended for axolotls because they are prone to eating small objects that can fit in their mouths, such as substrate particles like sand or gravel. Ingesting particles can block their gastrointestinal tracts and lead to life-threatening illnesses,” Dr. Hess told The Spruce Pets.

Using criteria from Dr. Hess and a wide range of research sources, we found the best filter for your axolotl. Our favorite for small tanks is the Penn-Plax Cascade Aquarium Canister Filter, for its ease of assembly and use, while we recommend the Aqueon Quietflow Canister Filter for larger tanks, thanks to its easy setup and quiet operation.

Our Top Picks

Best Overall, Small Tank:

Penn-Plax Cascade Aquarium Canister Filter 500 at Chewy

Jump to Review

Best Overall, Large Tank:

Aqueon Quietflow Canister Filter at Chewy

Jump to Review

Best Quiet Filter:

Eheim Classic 2211 Aquarium Canister Filter at Chewy

Jump to Review

Best Budget Filter:

Zoo Med Nano 30 External Canister Filter at Chewy

Jump to Review

Penn-Plax Cascade Aquarium Canister Filter 500

Chewy

View On Chewy View On Amazon

What We Like

Easy assembly
Affordable
Rotating valve taps make it easy to install in tight spaces
Quiet operation

What We Don't Like

Can be tricky to prime

This canister filter is used externally and offers mechanical, chemical and biological filtration. The two stackable trays, which come with coarse sponge and activated charcoal, are easy to access so you can customize filtration. This also makes maintenance a breeze because it’s not a hassle to disassemble and reassemble.

The unit has a push button primer and two independent valve taps that rotate 360 degrees, which fits into tight spaces and helps prevent hose kinks. The base is fairly sturdy so it won’t tip over easily if accidentally bumped.

It’s also one of the more quiet filters on the market, especially for the price point. There’s a slight hum from the motor, but it’s not overwhelming.

Price at time of Publish: $118

_{Dimensions11.5 x 9 x 13.5 inches |Gallons Per Minute/Flow Rate:115 |Appropriate for Tank Sizes:30 gallon and under}

Chewy

View On Chewy View On Amazon

What We Like

Set up is easy
Quiet operation

What We Don't Like

Water polishing cartridge must be replaced monthly

This canister filter includes three filtration baskets with foam pads for mechanical filtration, carbon for chemical filtration, and bio-balls and bio-ceramic rings for biological filtration. It’s also fairly quiet.

A water polishing basket with a replaceable carbon cartridge hangs on the back of the aquarium, which reduces how often the media baskets have to be replaced. This also provides one more layer of filtration before the water is put back into the tank.

The Aqueon Quietflow is available in three sizes, making it useful in tanks ranging from 30 to 150 gallons

Price at time of Publish: $110

_{Dimensions16.25 x 14.34 x 14 inches |Gallons Per Minute/Flow Rate:200 |Appropriate for Tank Sizes:40-55 gallons, 55-100 gallons, 100-150 gallons}

Eheim Classic 2211 Aquarium Canister Filter

Chewy

View On Chewy View On Amazon

What We Like

Compact size
Whisper quiet

What We Don't Like

Pricier than similar small-tank units

If your tank is located in a room where you don’t want a lot of noise, such as a bedroom, this filter is ideal for its extra-quiet operation. It’s nearly silent and also is energy efficient, using only 5 watts of energy while still providing mechanical, chemical and biological filtration.

The straightforward design makes maintenance and cleaning easy. It also has a small footprint, making it ideal in tight display quarters. The brand is known for its reliability and long life and is a favorite of aquarists.

Price at time of Publish: $105

_{Dimensions6 x 4.33 x 11.42 inches |Gallons Per Minute/Flow Rate:79 |Appropriate for Tank Sizes:40 gallons}

Zoo Med Nano 30 External Canister Filter

Chewy

View On Chewy

What We Like

Small footprint
High flow rate for small tanks
Rubber feet for stability

What We Don't Like

Doesn’t include filter media

与an 160 GPH flow rate, the Zoo Med Nano External Canister Filter is appropriate for up to a 30-gallon tank. It’s also relatively quiet for such a reasonable price point.

There’s a divider in the middle so you can use whatever medium you prefer. Even though it’s very small and lightweight, it is sturdy and resists tip-over when filled with media and water. Rubber feet on the bottom keep it from bouncing around or vibrating.

Price at time of Publish: $78

_{Dimensions7.5 x 7.5 x 12.4 inches |Gallons Per Minute/Flow Rate:160 |Tank Sizes:30 gallon}

Final Verdict

Our top pick for small tanks isPenn-Plax Cascade Aquarium Canister Filterfor its ease of assembly and use, while we likeAqueon Quietflow Canister Filterfor larger tanks for its easy setup and quiet operation.

Filter Types

Canister filterssit outside the tank and are pressurized to pump water through the filter media. When sized appropriately for the tank, without a strong flow, these are excellent filters for an axolotl tank, says Dr. Hess.
Chemical filtersare usually integrated within a canister filter. The chemical part of the filter works in addition to the mechanical and biological filters by using activated carbon to absorb and pull toxins out of the water. When present in an appropriately sized canister filter, chemical filters work great for axolotls.
Substrate filters, also known as an under-gravel filter, which sits inside the tank, pull water through the filter from below the substrate (typically sand or gravel) and outputs the water at the top of the tank.This type is not recommended for axolotls,says Dr. Hess.

Sizing

A filter must be properly sized to the volume of water in the tank, which should be a minimum tank size of 20 gallons. Tanks of 20 to 40 gallons are the typical range for axolotls. In general, axolotls are better housed alone, as they tend to chew on each other when housed together, says Dr. Hess.

Water Flow

The filter also should not produce a strong current from a high flow rate, which will stress the axolotl. “The flow should be gentle and not as strong as a stream or river,” says Dr. Hess.

Gallons Per Hour

Ideally, you want to have 5 water changes per hour for an axolotl tank. To ensure the flow rate isn’t too high for an axolotl, divide the flow rate by 5 to get the ideal tank size for an axolotl when using that filter.

As long as the tank is close to that ideal size, the flow rate for the axolotl should not be too high. So, for a 20-gallon tank, you need a filter with a flow rate of about 100 GPH but not more than 150 GPH, says Dr. Hess.

Writer Arricca SanSone researched the market based on criteria and recommendations from Laurie Hess, DVM, exotic animal veterinarian at Chewyand in private practice, as well as comparing product reviews. She has written extensively about nutrition and pet products for The Spruce Pets. Arricca’s has also taken deep dives into the bestwhisker fatigue bowls,puppy foods,dog ID tags, and even最好的养蜂套装.

The 6 Best Small Fish Tanks of 2023

The 4 Best Filters for Your Axolotl Tank

Best Overall, Small Tank

Penn-Plax Cascade Aquarium Canister Filter 500

Best Overall, Large Tank

Aqueon Quietflow Canister Filter

Best Quiet Filter

Eheim Classic 2211 Aquarium Canister Filter

Best Budget Filter

Zoo Med Nano 30 External Canister Filter

What to Look For in Axolotl Filters

Filter Types

Sizing

Water Flow

Gallons Per Hour

Why Trust The Spruce Pets

More fromThe Spruce Pets