Become a credit card member today!Fluval U3 Underwater Filter
Description
Where do fish go when they're feeling down? To the filter for some TLC! And if you've got a 24-40 gallon aquarium, the Fluval U3 Underwater Filter is the perfect match for your aquatic buddies. This filter is like a superhero for your tank, with three stages of filtration to keep the water crystal clear and healthy for your fish, marine creatures, or reptiles. Check out its awesome features:
- - Stage 1 foam removes all those pesky particles that can make your water cloudy and gross
- - Stage 2 poly/carbon cartridge traps debris and removes any impurities that might be lurking around
- - Stage 3 BIOMAX provides biological filtration, which basically means it creates a happy home for all the good bacteria that help keep your tank's ecosystem in balance
- - The 3-way flow control lets you adjust the output to fit your tank's needs - whether you need a gentle current or a stronger flow
- - The Flip-Top design makes maintenance a breeze - just pop it open, swap out the cartridges, and you're good to go
- - And of course, it comes with everything you need to get started - 2 foam pad cartridges, 2 carbon sponge pad cartridges, and Biomax nodes
Please note that the product information displayed is provided by manufacturers, suppliers and other third parties and is not independently verified by Petco.
Specifications
| SKU | 1288636 |
|---|---|
| Primary Brand | Fluval |
| Days to Ship | Usually Leaves Warehouse in 5-7 Business Days |
| Weight | 1 LBS |
| Personalized Item flag | No |
|---|
| Height | 10.5 IN |
|---|
Description
Where do fish go when they're feeling down? To the filter for some TLC! And if you've got a 24-40 gallon aquarium, the Fluval U3 Underwater Filter is the perfect match for your aquatic buddies. This filter is like a superhero for your tank, with three stages of filtration to keep the water crystal clear and healthy for your fish, marine creatures, or reptiles. Check out its awesome features:
- - Stage 1 foam removes all those pesky particles that can make your water cloudy and gross
- - Stage 2 poly/carbon cartridge traps debris and removes any impurities that might be lurking around
- - Stage 3 BIOMAX provides biological filtration, which basically means it creates a happy home for all the good bacteria that help keep your tank's ecosystem in balance
- - The 3-way flow control lets you adjust the output to fit your tank's needs - whether you need a gentle current or a stronger flow
- - The Flip-Top design makes maintenance a breeze - just pop it open, swap out the cartridges, and you're good to go
- - And of course, it comes with everything you need to get started - 2 foam pad cartridges, 2 carbon sponge pad cartridges, and Biomax nodes
Please note that the product information displayed is provided by manufacturers, suppliers and other third parties and is not independently verified by Petco.
Specifications
| SKU | 1288636 |
|---|---|
| Primary Brand | Fluval |
| Days to Ship | Usually Leaves Warehouse in 5-7 Business Days |
| Weight | 1 LBS |
Reviews
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Customers say
Customers overwhelmingly praise the filter for near-silent operation, exceptional water clarity, and reliable long-term performance. Most highlight crystal-clear results within hours, adjustable flow settings, and durability lasting two years or more. Many describe it as dependable and worth the investment, with several purchasing multiple units. However, some note that genuine replacement filter media is expensive and occasionally difficult to source. A few report premature mechanical failures or weak flow, though these issues are outweighed by widespread satisfaction and strong customer loyalty.
Most Helpful Favorable Review
Best bang for your buck
ErnieP
8 years ago
Couldn’t go wrong with this filter. Really user friendly when it comes time to c...
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23 PEOPLE FOUND THIS HELPFUL
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5
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4
Most Helpful Critical Review
Bought two, both broke
WaterTurtleOwner
5 years ago
Purchased one for our turtle tank. It worked great! Bought another for my niece ...
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11 PEOPLE FOUND THIS HELPFUL
Show Reviews:
3
2
and
1
Customer Images
Filter Reviews
5 Ratings-Only Reviews
Stopped working after 6 m
No, I do not recommend this product.
Bought two, both broke
No, I do not recommend this product.
Good Filter.
Yes, I recommend this product.
Great filter
No, I do not recommend this product.
Clears what quickly
Yes, I recommend this product.
Best bang for your buck
Yes, I recommend this product.
Fluval u3
Yes, I recommend this product.
Easy to use
Yes, I recommend this product.
Questions
Where do I get the replacement filters for this? The foam and carbon parts, I can't find any by fluval, I saw one from another company but not sure if it'll fit for this
I have 2 of these in a 45 gallon tank with 2 good-sized turtles, they have worked well for 5-6 years (6 months/yr) but lately not so good. Do they wear out?
What size tank is recommended for this type of filter? I have a 20 gallon for one turtle would this fit?
- You can get u2 for 20 gallons , but u3 May be better , it’s for 30 gallons tank
Helpful?
Looking forward something with very very low current. Is this it? If not can you recommend something that is? I know it’s adjustable but I really need barely no current.
- I have this in a well planted neon only tank ...I have it at the lowest possible setting and it’s been great for 5 years a also have bubbles in the corner because there is so little circulation........the filters are SILENT being underwater,too
Helpful?
is this similar to the hang on the side filters or something different? Used to have 10 Molly in a 29 gallon ended up being and babies got sucked into the hang over side filter. Wanting something that's not dangerous in case I get more and they do breed.
- Use a canister filter or under gravel filter... That shouldn't hurt the baby fishies.
Helpful?
would the fluval u4 be to big or to strong for a 40 breeder tank ?
- Thank you for your question. The Fluval U4 is rated for tank size of 34-65 gallons. However, depending on the specimens in the breeder tank, the flow may be too strong.
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Is it possible to run two Fluval U3 internal filters on a 75 gallon aquarium as stand alone filtration or as supplemental filtration?
- Thank you for your question. You can run 2 filter systems in an aquarium but it is generally not recommended. 2 filters rated for the aquarium volume combined will not be as efficient as a single unit rated for the same volume. Also, 2 filter systems could also cause odd circulation patterns in your aquarium and keep your water from being efficiently filtered.
Helpful?
Would this work in a 55 gallon tank that is about half full? I have 2 red-eared sliders in it.
- I would HIGHLY recommend using the Fluval4plus I have 5 RES’s. I keep 2 of the F4+ in my 120 gal tank with my 3 girls and I use one F4 + in my 55 gal with my 2 boys. They have lasted me YEARS! And I’ve only switched out twice. On my third switch out now because the impellers are what go out on these things, then the motor. Trash after that. I’ve had my RES babies for approx 15 years now.
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Custom Media
- fractalchemist Thank you for your question. We do not recommend using your own custom media for the U4 Fluval U Series Underwater Filter as it already comes with the specific media needed.
Helpful?
Pond Use
- Thank you for your question. This product is not intended for use outside and may not function properly. The output on the filter can be directed however you would like to suit your setup.
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