Best Undergravel Aquarium Filters in 2025

NOTHING LIKE OLD SCHOOL: The Clear-Free Premium Under Gravel Filter is air driven and utilizes an Air Pump (not included) to cycle crystal clear water throughout your aquarium, while keeping a crisp and neat look inside. This means there’s less “moving parts,” making for simplistic and easy maintenance. This filter is suitable for most 20 (long) – 29 gallon aquariums.

BIOLOGICAL, CHEMICAL, AND PHYSICAL FILTRATION: As air is pushed through the Air Stones and rises through the Lift Tubes, water is gently suctioned through gravel and the filter plates, allowing both air and water to pass through the Filt-a-Carb Activated Carbon Cartridges. When water continues to be drawn through, anaerobic bacteria collects and colonizes within the gravel and filter plates.

ALSO AERATES YOUR TANK: Since the Clear-Free Premium Under Gravel Filter is air driven through the use of Air Stones and an Air Pump (not included), it also aerates your tank. In essence, your aquarium is being filtered and aerated at the same time, though the same system! It’s a filter and bubbler in 1!

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 7 1/2-inch by 15-inch

The larger plate sizes reduce the number of plates required

The added strength of the UGF plates makes this filter most preferred by saltwater aquarists

Size: 12-inch by 48-inch

10 total disposable carbon cartridges

Filled with high-grade, activated carbon filter media

Disposable Carbon Cartridges keep aquariums sparkling clean

Country Of Origin: United States

Item Package Height: 16.25

Item Package Length: 23.0

Replacement part

Used as additions for existing filter systems

Designed to fit any Lee's Economy and Original Undergravel Filters

The larger plate sizes reduce the number of plates required

The added strength of the UGF plates makes this filter most preferred by saltwater aquarists

Size: 10-inch by 20-inch

This biological filter has a multi-level plate design.

The larger plate sizes reduce the number of plates required.

The added strength of the UGF plates makes this filter most preferred by saltwater aquarist.

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 12-inch by 24-inch

ADJUSTABLE FILTER: The Small World Fishbowl Under-Gravel Filter Kit is specifically designed for all drum or round bowls with a 4” or larger opening. If filter plate does not fit through the opening, you can break away the outer ring from between 2nd and 3rd levels, allowing for a better adjustments.

AIR-TECH PUMP: This Kit comes standard with an Air-Tech AT2K0 pump. In addition to being quiet, efficient, and reliable, this air pump is built with a strong motor that’s made to last. With silicone polymer flappers, a thick cover, and raised rubber feet, this pump will remain in place.

TOP-QUALITY CARBON: Supercharged with scientifically formulated Carbon, the media cartridge in this kit absorbs ammonia, nitrites, nitrates, and phosphates in a fast and timely manner, along with removing harmful chemicals and toxins, clearing up discolorations, and reducing foul odors from your fishbowl.

Circulate the water under gravel layer in order to reduce the corruption of gravel.

The gravel bed provides tremendous surface area for Nitrobacteria and keeps your water crystal clear.

The filter plate can be connected with air pump, filter pump, submersible power head and hang-on filter to increase the circulation and help with mechanical and chemical filtration.

connector 16mm

Pipe diameter 22mm

Circular bar tube is 16.6cm , Total 27 tubes

Lees under gravel uplifeet assembly 10.5-inch

Tubes come in sizes and the telescoping feature allows an additional 2-1/2-inch lift

Set include elbow, plate connector, telescoping ring and 1-inch dia Uplift tube

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 15-inch by 48-inch by 12-inch by 60-inch

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 6-inch by 12-inch

Product Name: Aquarium Under Gravel Filter 28 Pieces

Material : Plastic;Each Size : 140 x 70 x 12mm/5.5" x 2.8" x 0.5"(L*W*T)

Tube Size(Approx.) : 32 x 2.5cm/ 12.6" x 1"(H*D);Hose Hole Diameter : 5mm/0.2"

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 15-inch by 72-inch by 12-inch by 84-inch

Made of special quality plastic which resists splitting and cracking

Also has optional flow-thru set-up for use with a power head

Size: 15-inch by 36-inch

Simply place filter plates at the bottom of the tank and cover with gravel.

This undergravel filter hides from view for maximum aesthetics. Safe for use in both freshwater and saltwater tanks.

Material: Plastic. Size(LxWxH):Approx. 14x7x1.7cm/5.51x2.76x0.67inch

Aquarium filter Can be spliced at will with good water permeability.

Fish tank filter is very convenient to adopt the receiving type butt- joint installation.

Fish tank bottom filter plate is made of PVC material, slightly submerged and has good toughness.

The botton filter plate can activae the bottom bed, the deposition of undesirable substances.

Aquarium Filter is made of premium PVC material, slightly submerged and has good toughness.

Can be spliced the size you want. Good water permeability

100% brand new and high quality.

As a bottom filter plate accessories, easy to assemble.

Effortless setup and easy maintenance make this premium undergravel filter a must have for all home aquariums

High efficiency, eco-friendly and portable.

This undergravel filter hides from view for maximum aesthetics. Safe for use in both freshwater and saltwater tanks.

The filter plate circulates water through the gravel bed and oxygenates it for beneficial bacteria growth.

Used for: good accessory for breeding large dragon fish, sea fish and making fish tanks

Convenient and practical: very convenient to adopt the receiving type butt- joint installation.

Good water permeability: Can be spliced at will. Good water permeability