10 Best Aquarium Water Cleaner of 2026

Last updated on 05/12/2026

Advertising disclosure

Most Relevant

Most Relevant

Best Choice

hygger 360GPH Electric Aquarium Gravel Cleaner, 5 in 1 Automatic Fish Tank Cleaning Tool Set Vacuum Water Changer Sand Washer Filter Siphon Adjustable Length 15W

hygger 360GPH Electric Aquarium Gravel Cleaner, 5 in 1 Automatic Fish Tank Cleaning Tool Set Vacuum Water Changer Sand Washer Filter Siphon Adjustable Length 15W

hygger

Why we love it

Efficiently cleans aquarium corners.
Fast water changes save time.
Reusable filtration for clean water.

Main Highlights

CLEANING FUNCTION: Our sand cleaner have four spliced rigid tubes, which can be extended from 11.4 inches to 40.5 inches according to the tank. With brush heads, each corner of the fish tank can be cleaned. Aquarium gravel cleaner can also be used with the duckbill suction port to suck dirt from the corner of the fish tank, and the dung can be easily sucked away
WATER CHANGE FUNCTION: 4.92 ft super high head, and the water changer pump can provide a strong flow of up to 360GPH, the power of sand washer is sufficient to quickly change the water, saving half the time compared to manual. The starting water level can be as low as 2 inches, no water accumulation, and pumping as low as 0.3 inches
FILTRATION FUNCTION: The filter housing can filter the garbage in the water and make the clean water return to the tank. The fish tank can be filtered without changing water, such as washing sand, and the dirt is directly passed through the filter box. Filter sponge can be repeatedly cleaned and reused and can be replaced with other filter media
5 IN 1 MULTI-FUNCTION PUMP: Electric fish tank vacuum cleaner has high-density new plastic, detachable design, wear-resistant, lightweight, anti-fall. The adapter is AC 110V 60HZ, and the power supply has passed UL certification that is good to use. Independent switch control, easy to operate, no longer need to worry about unplugging the socket with wet hands
ACCESSORIES INCLUDE: functional accessories include 45 ° corner suction inlet（Sand washing head）, duckbill suction inlet(Debris vacuum), brush head, gravel washer(sand vacuum), 360 ° water intake strainer, filter housing; other accessories include: adapter ×1, independent switch ×1, water pump motor ×1, extension tube ×4, small connector ×1, Three-way valve ×1, handle ×1, wire slot ×4, outlet ×1, 2m water pipe ×1. 1x improved manual (with detailed use steps)

9.9

Exceptional

9.9

Exceptional

hygger

hygger 360GPH Electric Aquarium Gravel Cleaner, 5 in 1 Automatic Fish Tank Cleaning Tool Set Vacuum Water Changer Sand Washer Filter Siphon Adjustable Length 15W

Why we love it

Efficiently cleans aquarium corners.
Fast water changes save time.
Reusable filtration for clean water.

Main Highlights

CLEANING FUNCTION: Our sand cleaner have four spliced rigid tubes, which can be extended from 11.4 inches to 40.5 inches according to the tank. With brush heads, each corner of the fish tank can be cleaned. Aquarium gravel cleaner can also be used with the duckbill suction port to suck dirt from the corner of the fish tank, and the dung can be easily sucked away
WATER CHANGE FUNCTION: 4.92 ft super high head, and the water changer pump can provide a strong flow of up to 360GPH, the power of sand washer is sufficient to quickly change the water, saving half the time compared to manual. The starting water level can be as low as 2 inches, no water accumulation, and pumping as low as 0.3 inches
FILTRATION FUNCTION: The filter housing can filter the garbage in the water and make the clean water return to the tank. The fish tank can be filtered without changing water, such as washing sand, and the dirt is directly passed through the filter box. Filter sponge can be repeatedly cleaned and reused and can be replaced with other filter media
5 IN 1 MULTI-FUNCTION PUMP: Electric fish tank vacuum cleaner has high-density new plastic, detachable design, wear-resistant, lightweight, anti-fall. The adapter is AC 110V 60HZ, and the power supply has passed UL certification that is good to use. Independent switch control, easy to operate, no longer need to worry about unplugging the socket with wet hands
ACCESSORIES INCLUDE: functional accessories include 45 ° corner suction inlet（Sand washing head）, duckbill suction inlet(Debris vacuum), brush head, gravel washer(sand vacuum), 360 ° water intake strainer, filter housing; other accessories include: adapter ×1, independent switch ×1, water pump motor ×1, extension tube ×4, small connector ×1, Three-way valve ×1, handle ×1, wire slot ×4, outlet ×1, 2m water pipe ×1. 1x improved manual (with detailed use steps)

Value for Money

Tetra AquaSafe Plus, Aquarium Water Conditioner And Dechlorinator, 33.8 Ounces

Tetra AquaSafe Plus, Aquarium Water Conditioner And Dechlorinator, 33.8 Ounces

Tetra

Why we love it

Instantly safe for fish.
Removes harmful chemicals effectively.
Enhances fish healing and health.

Main Highlights

FOR FRESHWATER AND MARINE AQUARIUMS: Tetra AquaSafe Plus works instantly to make tap water safe for fish.
ADVANCED FORMULA: Neutralizes or removes harmful chlorine, chloramines and heavy metals.
PROTECTS FISH: Enhances protective slime coat to help wounds heal.
CLEAR AND HEALTHY WATER: With natural biopolymers and essential vitamins and minerals.
WATER CONDITIONER: Use when setting up a new aquarium, with monthly partial water changes, or evaporation replacement.

Tetra AquaSafe Plus, Aquarium Water Conditioner And Dechlorinator, 33.8 Ounces

Why we love it

Instantly safe for fish.
Removes harmful chemicals effectively.
Enhances fish healing and health.

Main Highlights

FOR FRESHWATER AND MARINE AQUARIUMS: Tetra AquaSafe Plus works instantly to make tap water safe for fish.
ADVANCED FORMULA: Neutralizes or removes harmful chlorine, chloramines and heavy metals.
PROTECTS FISH: Enhances protective slime coat to help wounds heal.
CLEAR AND HEALTHY WATER: With natural biopolymers and essential vitamins and minerals.
WATER CONDITIONER: Use when setting up a new aquarium, with monthly partial water changes, or evaporation replacement.

UPETTOOLS Aquarium Gravel Cleaner - Electric Automatic Removable Vacuum Water Changer Sand Algae Cleaner Filter Changer 110V/28W

UPETTOOLS Aquarium Gravel Cleaner - Electric Automatic Removable Vacuum Water Changer Sand Algae Cleaner Filter Changer 110V/28W

UPETTOOLS

Why we love it

Multifunctional for all tanks.
Powerful suction cleans efficiently.
Adjustable length for convenience.

Main Highlights

【Upgraded 6-in-1 Multi-Functional Aquarium Gravel Cleaner】This upgraded gravel vacuum integrates six essential functions: water changing, sand washing, debris removal, water filtration, water showering, and flow control. Designed for use in both freshwater and saltwater aquariums, it is compatible with tanks of various depths and water volumes.
【High-Efficiency 28W Pump with 1700L/H Flow Rate】Equipped with a 110V/28W high-torque motor, the pump delivers a maximum flow rate of 1700 liters per hour (L/H). It can drain a 180-gallon (681L) tank in approximately 30 minutes under optimal conditions. The adjustable flow valve allows precise control of suction strength for gentle or deep cleaning.
【Powerful Cleaning Performance】The strong suction effectively removes fish waste, uneaten food, algae, and fine debris from gravel and substrate without disturbing beneficial bacteria. Ideal for routine maintenance and deep cleaning, it ensures efficient water changes and a healthier tank environment.
【Adjustable Telescopic Tube for Universal Fit】The telescopic cleaning tube extends from 23.6 inches (60 cm) to 37.7 inches (96 cm), accommodating water depths from 13.7 inches (35 cm) to 47.2 inches (120 cm). The ergonomic design allows comfortable operation in shallow or deep tanks, with secure locking mechanisms to prevent accidental retraction.
【3-Year Warranty & 24/7 Customer Support】We stand behind our product with a 3-year warranty covering manufacturing defects. Our professional technical team provides round-the-clock support. If you have any questions or encounter issues, please contact us directly—we respond within 24 hours and are committed to your satisfaction.

UPETTOOLS Aquarium Gravel Cleaner - Electric Automatic Removable Vacuum Water Changer Sand Algae Cleaner Filter Changer 110V/28W

Why we love it

Multifunctional for all tanks.
Powerful suction cleans efficiently.
Adjustable length for convenience.

Main Highlights

【Upgraded 6-in-1 Multi-Functional Aquarium Gravel Cleaner】This upgraded gravel vacuum integrates six essential functions: water changing, sand washing, debris removal, water filtration, water showering, and flow control. Designed for use in both freshwater and saltwater aquariums, it is compatible with tanks of various depths and water volumes.
【High-Efficiency 28W Pump with 1700L/H Flow Rate】Equipped with a 110V/28W high-torque motor, the pump delivers a maximum flow rate of 1700 liters per hour (L/H). It can drain a 180-gallon (681L) tank in approximately 30 minutes under optimal conditions. The adjustable flow valve allows precise control of suction strength for gentle or deep cleaning.
【Powerful Cleaning Performance】The strong suction effectively removes fish waste, uneaten food, algae, and fine debris from gravel and substrate without disturbing beneficial bacteria. Ideal for routine maintenance and deep cleaning, it ensures efficient water changes and a healthier tank environment.
【Adjustable Telescopic Tube for Universal Fit】The telescopic cleaning tube extends from 23.6 inches (60 cm) to 37.7 inches (96 cm), accommodating water depths from 13.7 inches (35 cm) to 47.2 inches (120 cm). The ergonomic design allows comfortable operation in shallow or deep tanks, with secure locking mechanisms to prevent accidental retraction.
【3-Year Warranty & 24/7 Customer Support】We stand behind our product with a 3-year warranty covering manufacturing defects. Our professional technical team provides round-the-clock support. If you have any questions or encounter issues, please contact us directly—we respond within 24 hours and are committed to your satisfaction.

KloudAway Freshwater Aquarium Water Clarifier - Clears Cloudy Water, Water Clarifier for Fish Tank, Made in USA, Aquatic Experts, (500 ml)

KloudAway Freshwater Aquarium Water Clarifier - Clears Cloudy Water, Water Clarifier for Fish Tank, Made in USA, Aquatic Experts, (500 ml)

Aquatic Experts

11% Off

Why we love it

Fast-acting clarity for aquariums.
Safe for all aquatic life.
Targets debris, not algae.

Main Highlights

FAST- ACTING - KloudAway quickly clears cloudy or hazy aquarium water by CLUMPING FLOATING PARTICLES together making them large enough to be trapped by your aquariums' mechanical filter. To remove these particles from the water your aquarium must have a mechanical filter.
CUTTING EDGE FORMULA - Our advanced fish tank water clarifier is targeting unsightly particles in water such as uneaten fish food, dust and other debris to produce crystal clear water. KLOUDAWAY DOES NOT WORK ON "GREEN WATER" as algae continues to multiply.
SAFE AND EFFECTIVE - Our cloudy water treatment is SAFE FOR all types of FRESHWATER FISH, TURTLES, PLANTS, SHRIMP and OTHER INVERTEBRATES and has no effect on the beneficial bacteria in your aquarium's biological filtration.
REMARKABLE RESULTS! Use our aquarium clarifier to maintain sparkling clear water in your freshwater aquarium. For exact details of how to use KloudAway, causes of cloudy water and much more, WATCH OUR VIDEO "Clear Aquarium Water Fast"
Water testing is recommended. Cloudy water is often caused by New Tank Syndrome, which can cause dangerously high levels of ammonia and nitrite. Protect your fish from ammonia spikes with TankFirst Water Conditioner!

KloudAway Freshwater Aquarium Water Clarifier - Clears Cloudy Water, Water Clarifier for Fish Tank, Made in USA, Aquatic Experts, (500 ml)

11% Off

Why we love it

Fast-acting clarity for aquariums.
Safe for all aquatic life.
Targets debris, not algae.

Main Highlights

FAST- ACTING - KloudAway quickly clears cloudy or hazy aquarium water by CLUMPING FLOATING PARTICLES together making them large enough to be trapped by your aquariums' mechanical filter. To remove these particles from the water your aquarium must have a mechanical filter.
CUTTING EDGE FORMULA - Our advanced fish tank water clarifier is targeting unsightly particles in water such as uneaten fish food, dust and other debris to produce crystal clear water. KLOUDAWAY DOES NOT WORK ON "GREEN WATER" as algae continues to multiply.
SAFE AND EFFECTIVE - Our cloudy water treatment is SAFE FOR all types of FRESHWATER FISH, TURTLES, PLANTS, SHRIMP and OTHER INVERTEBRATES and has no effect on the beneficial bacteria in your aquarium's biological filtration.
REMARKABLE RESULTS! Use our aquarium clarifier to maintain sparkling clear water in your freshwater aquarium. For exact details of how to use KloudAway, causes of cloudy water and much more, WATCH OUR VIDEO "Clear Aquarium Water Fast"
Water testing is recommended. Cloudy water is often caused by New Tank Syndrome, which can cause dangerously high levels of ammonia and nitrite. Protect your fish from ammonia spikes with TankFirst Water Conditioner!

Fluval Waste Control Biological Cleaner, Aquarium Water Treatment, 8.4 Oz., A8355

Fluval Waste Control Biological Cleaner, Aquarium Water Treatment, 8.4 Oz., A8355

Fluval

Why we love it

Cleans water naturally and effectively.
Perfect for new aquarium setups.
Works in freshwater and saltwater.

Main Highlights

Care for Your Habitat: All-natural water care reduces organic waste and overall tank maintenance by effectively cleaning interior surfaces. Treats up to 500 gallons of water.
Ideal for New Aquariums: Extremely effective when setting up a new aquarium or introducing new fish to an existing one and useful during water changes and filter media changes, when organic waste is building up.
All-Natural Care: Infused with Bio Scrubbers that breaks down waste and promotes clean water and living conditions.
Proper Care: For best results, use in combination with Fluval Cycle Biological Enhancer to prevent/control potential increases in ammonia and nitrite caused by breakdown of organic matter.
Additional Features: Can be used in both freshwater and saltwater aquariums.

Fluval Waste Control Biological Cleaner, Aquarium Water Treatment, 8.4 Oz., A8355

Why we love it

Cleans water naturally and effectively.
Perfect for new aquarium setups.
Works in freshwater and saltwater.

Main Highlights

Care for Your Habitat: All-natural water care reduces organic waste and overall tank maintenance by effectively cleaning interior surfaces. Treats up to 500 gallons of water.
Ideal for New Aquariums: Extremely effective when setting up a new aquarium or introducing new fish to an existing one and useful during water changes and filter media changes, when organic waste is building up.
All-Natural Care: Infused with Bio Scrubbers that breaks down waste and promotes clean water and living conditions.
Proper Care: For best results, use in combination with Fluval Cycle Biological Enhancer to prevent/control potential increases in ammonia and nitrite caused by breakdown of organic matter.
Additional Features: Can be used in both freshwater and saltwater aquariums.

API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle

API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle

API

Why we love it

Enhances fish health effectively.
Promotes safe water conditions.
Aloe Vera aids healing process.

Main Highlights

Contains one (1) API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
Makes tap water safe and protects fish with dual-action formula
Removes chemicals from tap water that are harmful to fish
Replaces fish’s protective coat damaged by handling or fish fighting with healing power of Aloe Vera extract
Use when adding or changing water, when adding new fish and when fish are sick or injured
Instructions: Add 5 ml. for each 10 gallons of aquarium water. Double the dose to replace slime coat and to repair damaged skin and fins

API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle

Why we love it

Enhances fish health effectively.
Promotes safe water conditions.
Aloe Vera aids healing process.

Main Highlights

Contains one (1) API STRESS COAT Aquarium Water Conditioner 16-Ounce Bottle
Makes tap water safe and protects fish with dual-action formula
Removes chemicals from tap water that are harmful to fish
Replaces fish’s protective coat damaged by handling or fish fighting with healing power of Aloe Vera extract
Use when adding or changing water, when adding new fish and when fish are sick or injured
Instructions: Add 5 ml. for each 10 gallons of aquarium water. Double the dose to replace slime coat and to repair damaged skin and fins

QZQ Aquarium Gravel Cleaner [2026 Edition] Vacuum Fish Tank Vacuum Cleaner Tools for Aquarium Water Changer with Aquarium Thermometers Fish Net kit Use for Fish Tank Cleaning Gravel and Sand

QZQ Aquarium Gravel Cleaner [2026 Edition] Vacuum Fish Tank Vacuum Cleaner Tools for Aquarium Water Changer with Aquarium Thermometers Fish Net kit Use for Fish Tank Cleaning Gravel and Sand

QZQ

14% OffLimited time deal

Why we love it

Multi-functional for complete cleaning.
Safe and silent operation.
Easy installation for convenience.

Main Highlights

Mufti-functional cleaning kit: Aquarium gravel vacuum cleaner kit is a mufti-functional aquarium cleaner that uses (adopts)the siphon design principle, which includes the aquarium, aquarium sand washing, algae scraping, fish excrement cleaning, aquarium residual debris, and aquarium water changing. Quick water change gives fish (provides)a clean and comfortable aquarium living environment.
New safety design: new manual press design, no electricity required and silent while working. Fish tank cleaning tools uses a high-quality pressure resistant air bag, durable, super strong siphon pressure can quickly draw out the muddy water in the fish tank. The aquarium vacuum pipe has a filter net attached to the filter basket to block the blockage caused by the suction of gravel, while preventing your cute fish and the small gravel in the bathtub from being sucked out of the tank.
Easy to install: This newly upgraded aquarium vacuum is easier to use than traditional fish tank vacuum. Simply hold the handle and press several times until you see water begin to flow out. You can also use a tube to agitate the gravel in the aquarium, causing fish manure, food debris, etc. to drain out of the aquarium with the current. The aquarium cleaning tools is securely attached to the aquarium so you can easily release your hands.
A wide range of multi-combination accessories: aquarium cleaner vacuum crusher is suitable for different types and sizes of fish tanks, equipped with 2 water pipes and 1 joint, press pump, water flow clip, water pipe clip extended outlet hose, aquarium temperature stickers, fishing nets, plastic algae scraping plate, and detailed aquarium vacuum pump manual.
Easy to use: The aquarium cleaning kit dust and water changer is hand-held, easy to use and operate, the aquarium cleaners can work stably and efficiently without electricity and without noise, which greatly saves your time and brings more convenience for fish tank cleaning.

QZQ Aquarium Gravel Cleaner [2026 Edition] Vacuum Fish Tank Vacuum Cleaner Tools for Aquarium Water Changer with Aquarium Thermometers Fish Net kit Use for Fish Tank Cleaning Gravel and Sand

14% OffLimited time deal

Why we love it

Multi-functional for complete cleaning.
Safe and silent operation.
Easy installation for convenience.

Main Highlights

Mufti-functional cleaning kit: Aquarium gravel vacuum cleaner kit is a mufti-functional aquarium cleaner that uses (adopts)the siphon design principle, which includes the aquarium, aquarium sand washing, algae scraping, fish excrement cleaning, aquarium residual debris, and aquarium water changing. Quick water change gives fish (provides)a clean and comfortable aquarium living environment.
New safety design: new manual press design, no electricity required and silent while working. Fish tank cleaning tools uses a high-quality pressure resistant air bag, durable, super strong siphon pressure can quickly draw out the muddy water in the fish tank. The aquarium vacuum pipe has a filter net attached to the filter basket to block the blockage caused by the suction of gravel, while preventing your cute fish and the small gravel in the bathtub from being sucked out of the tank.
Easy to install: This newly upgraded aquarium vacuum is easier to use than traditional fish tank vacuum. Simply hold the handle and press several times until you see water begin to flow out. You can also use a tube to agitate the gravel in the aquarium, causing fish manure, food debris, etc. to drain out of the aquarium with the current. The aquarium cleaning tools is securely attached to the aquarium so you can easily release your hands.
A wide range of multi-combination accessories: aquarium cleaner vacuum crusher is suitable for different types and sizes of fish tanks, equipped with 2 water pipes and 1 joint, press pump, water flow clip, water pipe clip extended outlet hose, aquarium temperature stickers, fishing nets, plastic algae scraping plate, and detailed aquarium vacuum pump manual.
Easy to use: The aquarium cleaning kit dust and water changer is hand-held, easy to use and operate, the aquarium cleaners can work stably and efficiently without electricity and without noise, which greatly saves your time and brings more convenience for fish tank cleaning.

API ACCU-CLEAR Freshwater Aquarium Water Clarifier 8-Ounce Bottle

API ACCU-CLEAR Freshwater Aquarium Water Clarifier 8-Ounce Bottle

API

Why we love it

Clears cloudy aquarium water quickly.
Enhances filter efficiency significantly.
Easy to use weekly.

Main Highlights

Contains one (1) API ACCU-CLEAR Freshwater Aquarium Water Clarifier 8-Ounce Bottle
Clears cloudy aquarium water
Clumps floating particles into large clusters that can be easily removed by an aquarium filter
Works fast and maximizes filter efficiency
Use weekly and when cloudy water is observed in freshwater aquariums only

API ACCU-CLEAR Freshwater Aquarium Water Clarifier 8-Ounce Bottle

Why we love it

Clears cloudy aquarium water quickly.
Enhances filter efficiency significantly.
Easy to use weekly.

Main Highlights

Contains one (1) API ACCU-CLEAR Freshwater Aquarium Water Clarifier 8-Ounce Bottle
Clears cloudy aquarium water
Clumps floating particles into large clusters that can be easily removed by an aquarium filter
Works fast and maximizes filter efficiency
Use weekly and when cloudy water is observed in freshwater aquariums only

API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle

API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle

API

Why we love it

Neutralizes harmful tap water chemicals.
Prevents fish health issues.
Super concentrated formula for efficiency.

Main Highlights

Contains one (1) API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle
Neutralizes chlorine, chloramines and other chemicals to make tap water safe for fish
Prevents tap water chemicals from causing gill destruction, tissue irritation and fish death
Super strength, high concentration formula
Use when adding or changing water and when adding new fish to freshwater and saltwater aquariums
Add 1 ml. for each 20 gallons of aquarium water.

API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle

Why we love it

Neutralizes harmful tap water chemicals.
Prevents fish health issues.
Super concentrated formula for efficiency.

Main Highlights

Contains one (1) API TAP WATER CONDITIONER Aquarium Water Conditioner 16-Ounce Bottle
Neutralizes chlorine, chloramines and other chemicals to make tap water safe for fish
Prevents tap water chemicals from causing gill destruction, tissue irritation and fish death
Super strength, high concentration formula
Use when adding or changing water and when adding new fish to freshwater and saltwater aquariums
Add 1 ml. for each 20 gallons of aquarium water.

Tetra Water Cleaner Gravel Siphon for Aquariums, Easily Clean Freshwater Aquariums

Tetra Water Cleaner Gravel Siphon for Aquariums, Easily Clean Freshwater Aquariums

Tetra

Why we love it

Effortless cleaning for aquariums.
Compatible with 55-gallon tanks.
Includes all necessary setup tools.

Main Highlights

TETRA WATER CLEANER: Gravel siphon used to easily clean aquariums.
COMPATIBLE AQUARIUM SIZE: For aquariums up to 55 gallons.
MAKES MONTHLY WATER CHANGES EASY: It only takes 30 minutes to replace 30% of water every 30 days.
REMOVE DEBRIS: Siphons are a great way to easily remove debris from gravel by moving the water cleaner throughout the gravel.
INCLUDED: Tetra Water Cleaner comes with gravel siphon, priming bulb and clip for bucket for a simple set up.

Tetra Water Cleaner Gravel Siphon for Aquariums, Easily Clean Freshwater Aquariums

Why we love it

Effortless cleaning for aquariums.
Compatible with 55-gallon tanks.
Includes all necessary setup tools.

Main Highlights

TETRA WATER CLEANER: Gravel siphon used to easily clean aquariums.
COMPATIBLE AQUARIUM SIZE: For aquariums up to 55 gallons.
MAKES MONTHLY WATER CHANGES EASY: It only takes 30 minutes to replace 30% of water every 30 days.
REMOVE DEBRIS: Siphons are a great way to easily remove debris from gravel by moving the water cleaner throughout the gravel.
INCLUDED: Tetra Water Cleaner comes with gravel siphon, priming bulb and clip for bucket for a simple set up.