Fluval Aquarium Underwater Filter, 24-40 gal
By Fluval
$29.39 (-63%) Chewy Price
$79.99 List Price
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About This Item
Details
- Optimal water filtration system for aquariums that ensures proper oxygenation for clear water and a healthy environment.
- Fine foam pad traps small debris while bio-foam captures larger debris and nitrifying bacteria.
- Adjustable 3-way flow control—top output for circulation and oxygenation, integrated spray bar for a gentle even flow, and bottom output for deepwater agitation.
- Convenient flip-top lid allows for quick and easy access to filter cartridge for maintenance or replacement.
- Ideal for freshwater, saltwater and reptile environments.
Instructions
Learn More About Fluval From Our Team of Experts
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20 Customer Questions
How many inches of water can this be placed in? I want to use it for a very shallow hatchling turtle enclosure.
Answer by Kitn • Nov 25, 2025
You can mount the filter horizontally in your tank. I have it horizontally in my twenty gallon and it's a dream. My corey's play in the jets all the time
Can I use this for my Betta fish, how fast is the flow?
Answer by • Jan 10, 2018
This Filter allows for adjustable flow and will be suitable for a tank with a Betta.
What size is best recommended for a 75 gallon tank? Thank you!
Answer by • Feb 04, 2018
The U1 is suitable for up to 15 gallon tanks, the U2 is for 12-30 gallon tanks, the U3 is for 24-40 gallon tanks and the U4 is perfect for 34-65 gallon aquariums. At this time this model does not have an option for a 75 gallon tank.
How often do you recommend a filter change?
Answer by Alexis W • Apr 29, 2024
Filter foam pads should be replaced every 3-6 months and the impellar should be replaced yearly for optimal performance.