5 gallon fish tank filter
Skip itSoft demand (-10.5% this quarter) — this niche doesn't clear our bar today.
Quality gap
Great4.1★avg incumbent rating — lower means beatable quality
Brand share
Good70%top-5 brand share — brands hold most of the demand
Competition
Good52%top-5 click share — leaders hold, buyers still browse
Conversion
Good4.3%search→purchase rate — share of searches ending in a sale
Returns
Okay3.2%return rate — above 6% kills the launch gate
Price range
Okay$5.91–$22.36cheapest to priciest tracked listing — scored on the share inside $15–$100
Avg price
Okay$10.88avg listing price — sweet spot $15–$100
Review moat
Okay2,711.66avg incumbent reviews — the moat a new listing must climb
Market size
Okay$102K$102K/yr · 217K searches
Growth
Bad-10.5%90-day search growth — must beat 0% to launch
According to Flapen's Amazon United States niche tracking, 5 gallon fish tank filter is a $102K/yr Amazon United States market (217K searches/yr). The top 5 brands hold 70% of demand. Demand peaks in Jul–Aug. Verdict: Skip it — 46/100.
Data updated Jul 17, 2026 · scored weekly · How we score niches
5 gallon fish tank filter market data
- Units sold / yr
- 10K–13K
- avg 250–500/product
- Revenue / yr
- $109K–$136K
- units × avg price
- Launch success
- 13%
- 1 of 8 new (360d)
- Conversion rate
- 4.3%
- Avg BSR
- #90
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 75%
- Out of stock
- 4.1%
- Avg brand age
- 40 months
- Avg seller age
- 171 days
Competition & brand share
The top 5 products take 52% of clicks — established leaders, but buyers still shop beyond them.Brands
20 falling
Sellers
35
Top-5 brand share
70%
Top 20: 100%
Top-5 click share
52%
Top 20: 87%
Open market
23%
- Tetra23%
- NICREW22%
- DaToo9%
- Aqueon8%
- Pawfly8%
- Novique7%
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -10.5% search growth over the last 90 days.Peak months: Jul, Aug · busiest ÷ quietest = 2.0×
Top 5 gallon fish tank filter search terms
- 3 gallon fish tank filter28K/yr
- betta fish filter18K/yr
- mini aquarium filter20K/yr
- 5 gallon tank filter16K/yr
- 2.5 gallon fish tank filter17K/yr
- betta tank filter14K/yr
- 2 gallon fish tank filter16K/yr
- beta fish filter11K/yr
- mini fish tank filter11K/yr
- 5 gallon filter9K/yr
Top 5 gallon fish tank filter products on Amazon
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
All 32 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Tetra Whisper 4i Internal Power Filter Filtration for Aquariums Between 1 and 4 Gallons
Tetra$12.354.3★22,392 rev
NICREW Slim Aquarium Filter Quiet Fish Tank HOB Filters for up to 5 Gallon Aquariums Adjustable Flow 42 GPH 3W
NICREW$12.344.1★2,763 rev
Tetra Whisper Internal Power Filter Medium Bio-Bag Filter Cartridges 3-Stage Filtration 5-10 gal
Tetra$15.614.3★22,392 rev
DaToo Aquarium Power Filter In-Tank Ultra Silent Small Fish Tank Filter 3W For Aquarium 1 to 10 Gallon Tank 1 Yr Warranty
DaToo$7.754.0★3,198 rev
Novique HOB Slim Aquarium Filter for Up to 5 Gallon Tank Ultra-Quiet Fish Tank Power Filter Flow Adjustable Suitable for Saltwater and Freshwater 42 GPH 3W
Novique$8.963.9★119 rev
Newest
by launch date
HSIFMATE Small Fish Tank Filter Hang on Filter for 1-5 Gal Nano Aquarium Ultra Quiet Power Filter with Aeration & Oil Skimmer Adjustable Flow for Betta Shrimp Tank
HSIFMATE$11.5711 rev
Carefree Fish Aquarium Small Sponge Bubble Filter with Fish Poops Collector Quiet for 3~8Gal Fish Tank for Saltwater and Freshwater(Not Include Air Pump)
Carefree Fish$9.8230 rev
12-Pack EF-S Replacement Filter Cartridges for BF5 BettaFlo Aquarium Professional Triple Filtration to Keep Water Crystal Clear & Fish Healthy High-Density Activated Carbon Refills for Fish Tank
Meidier$7.2475 rev
Pawfly Aquarium Filter 3 W Small Fish Tank Filter Internal Submersible Aquarium Filter with Foam & Adjustable Water Pump Quiet Filter for 8-20 Gallon Fish Tanks
Pawfly$11.6331 rev
QiQiWader Small Aquarium Filter Fish Tank Filter Suitable for 3-10 Gallon Fish Tanks 3W 80GPH with Two Modes Switching Function.
QiQiWader$16.8098 rev
Trending
90-day click momentumCarefree Fish Aquarium Small Sponge Bubble Filter with Fish Poops Collector Quiet for 3~8Gal Fish Tank for Saltwater and Freshwater(Not Include Air Pump)
Carefree Fish$9.824.0★
HSIFMATE Small Fish Tank Filter Hang on Filter for 1-5 Gal Nano Aquarium Ultra Quiet Power Filter with Aeration & Oil Skimmer Adjustable Flow for Betta Shrimp Tank
HSIFMATE$11.573.6★
12-Pack EF-S Replacement Filter Cartridges for BF5 BettaFlo Aquarium Professional Triple Filtration to Keep Water Crystal Clear & Fish Healthy High-Density Activated Carbon Refills for Fish Tank
Meidier$7.244.1★
Pawfly Aquarium Filter 3 W Small Fish Tank Filter Internal Submersible Aquarium Filter with Foam & Adjustable Water Pump Quiet Filter for 8-20 Gallon Fish Tanks
Pawfly$11.633.8★
Novique HOB Slim Aquarium Filter for Up to 5 Gallon Tank Ultra-Quiet Fish Tank Power Filter Flow Adjustable Suitable for Saltwater and Freshwater 42 GPH 3W
Novique$8.963.9★
What buyers say about 5 gallon fish tank filter
What buyers praise and complain about, mined from review topics.What buyers love
“Excellent filter”
“Very affordable”
“Amazing fit”
“Great looking product”
“Cleaning is straightforward”
“Came as advertised”
“still get good water flow”
“Gets good flow”
“This is a strong”
“easy to use”
What buyers complain about
“Breaks easily”
“Does not filter good”
“it's most likely not going to fit very well”
“Complete garbage”
“Not effective”
“didnt really clean well”
“It leaks”
“didn't siphon any water”
“feels flimsy”
“Instructions would have been nice”
Top return reasons
Common questions
- Is 5 gallon fish tank filter profitable to sell on Amazon United States?
- The niche generates $102K/yr across 32 tracked products. 1 of 8 products launched in the last 360 days are still selling. 90-day search growth is -10.5%. Flapen's verdict: Skip it (46/100).
- How competitive is the 5 gallon fish tank filter niche?
- 20 brands and 35 sellers compete. The top 5 products take 52% of clicks and top 5 brands hold 70% of demand.
- What do buyers complain about in 5 gallon fish tank filter?
- Top complaints mined from reviews: Durability, Filtration, Size-Overall. The return rate is 3.2%.
- When does demand for 5 gallon fish tank filter peak?
- Demand peaks in Jul–Aug; the busiest month runs 2.0× the quietest.
- What does it cost to enter the 5 gallon fish tank filter niche?
- Listings span $5.91–$22.36; the average listing price is $10.88 (sweet spot $15–$100). The average incumbent carries 2,712 reviews — the moat a new listing must climb.