---
title: "Top Fin Ef-s Filter Cartridges — $110K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/pet-supplies/top-fin-ef-s-filter-cartridges"
last_updated: "2026-07-22T20:52:00.552Z"
locale: en
meta:
description: "Niche score 37/100 · $110K/yr market · 48K searches/yr · $11.00 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 37/100 · $110K/yr market · 48K searches/yr · $11.00 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Top Fin Ef-s Filter Cartridges — $110K/yr Amazon US Niche (2026) - Flapen"
---
# **top fin ef-s filter cartridges**
**Skip it**
Brand-locked demand (top 5 brands take 100% of clicks) — this niche doesn't clear our bar today.
Market size 26Growth 23Conversion 100Competition 14Returns 79Price range 32Avg price 42Brand share 0Review moat 56Quality gap 37
**Conversion**
**Incredible****21.1%**
search→purchase rate — share of searches ending in a sale
**Returns**
**Great****1.8%**
return rate — above 6% kills the launch gate
**Review moat**
**Good****1,274.78**
avg incumbent reviews — the moat a new listing must climb
**Avg price**
**Okay****$11.00**
avg listing price — sweet spot $15–$100
**Quality gap**
**Okay****4.5★**
avg incumbent rating — lower means beatable quality
**Price range**
**Okay****$7.24–$18.66**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Market size**
**Okay****$110K**
$110K/yr · 48K searches
**Growth**
**Bad****-4.5%**
90-day search growth — must beat 0% to launch
**Competition**
**Bad****84%**
top-5 click share — a locked-up shelf
**Brand share**
**Bad****100%**
top-5 brand share — brand-locked demand
According to Flapen's Amazon United States niche tracking, top fin ef-s filter cartridges is a $110K/yr Amazon United States market (48K searches/yr). The top 5 brands hold 100% of demand. Demand peaks in Jan–Nov. Verdict: Skip it — 37/100.
Data updated Jul 17, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **top fin ef-s filter cartridges market data**
- **Units sold / yr**
- **8K–10K**
- avg 750–1,000/product
- **Revenue / yr**
- **$88K–$110K**
- units × avg price
- **Launch success**
- **—**
- 0 of 1 new (360d)
- **Conversion rate**
- **21.1%**
- **Avg BSR**
- **#97**
- **Page quality**
- **0%**
- **Prime**
- **100%**
- **Sponsored**
- **89%**
- **Out of stock**
- **0.0%**
- **Avg brand age**
- **56 months**
- **Avg seller age**
- **145 days**
## **Competition & brand share**
The top 5 products capture 84% of clicks — a locked-up shelf that new listings rarely crack.
**Brands**
**5 **—flat
**Sellers**
**48**
**Top-5 brand share**
**100%**
Top 20: 100%
**Top-5 click share**
**84%**
Top 20: 100%
**Open market**
**0%**
- HiTauing73% - Top Fin11% - Zuqqony8% - driamor4% - Meidier4%
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — -4.5% search growth over the last 90 days.
2K1KPrime Day '25Spike '25Black Friday '25 seasonSepDecMarJunAugNovMarMay
Peak months: Jan, Nov · busiest ÷ quietest = 1.9×
[**Open Trend **](https://flapen.com/research/us/pet-supplies/top-fin-ef-s-filter-cartridges/trend)
## **Top top fin ef-s filter cartridges search terms**
- **ef-s fish tank filter**12K/yr-1.4%19.8% conv. - **top fin ef-s filter cartridges**11K/yr-2.3%21.1% conv. - **fish tank filter replacement pads**5K/yr+24.5%1.6% conv. - **topfin ef-s filter cartridge**4K/yr-14.3%24.1% conv. - **5 gallon fish tank filter cartridge**4K/yr+18.8%2.6% conv. - **efs fish tank filter**3K/yr+2.2%19.8% conv. - **top fin ef-s element filter cartridge**3K/yr-24.6%22.3% conv. - **ef-s filter cartridges fish tank**3K/yr-5.0%19.8% conv. [**All search terms **](https://flapen.com/research/us/pet-supplies/top-fin-ef-s-filter-cartridges/search-terms)
## **Top top fin ef-s filter cartridges 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.
0%15%$17K30%$33K45%$50K60%$66K101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 9 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**HiTauing 8 Pack EF-S Filter Cartridges for EF-S Element and BF5 BETTAFLO**HiTauing**$8.69**4.6★3,205 rev](https://www.amazon.com/dp/B0B9656RGN) [2**Top Fin EF-S Element Filter Cartridges (6 Count) for Fish Tank**Top Fin**$18.66**4.7★1,320 rev](https://www.amazon.com/dp/B08JJ3J41G) [3**HiTauing 12 Packs Filter Cartridge Compatible with EF-S Element and BF5 BETTAFLO Filter**HiTauing**$12.64**4.6★1,138 rev](https://www.amazon.com/dp/B09ZKWVMHC) [4**HiTauing 6 Pack EF-S Filter Cartridges for EF-S Element and BF5 BETTAFLO**HiTauing**$7.70**4.6★3,205 rev](https://www.amazon.com/dp/B09D39WL1B) [5**HiTauing 15 Packs Filter Cartridge for EF-S Element and BF5 BETTAFLO**HiTauing**$13.53**4.6★1,138 rev](https://www.amazon.com/dp/B0B967VBJW)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**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**$7.24**75 rev5mo ago](https://www.amazon.com/dp/B0GJ768YK9) [**Zuqqony 8 Pack Filter Cartridges for Filter Replacement Filter Cartridges for Top Fin EF-S Element and BF5 BETTAFLO**Zuqqony**$8.77**523 rev2y ago](https://www.amazon.com/dp/B0CZ87KZML) [**15 Pack Filter Cartridges for Filter Replacement Filter Cartridges for Top Fin EF-S Element and BF5 BETTAFLO**Zuqqony**$13.65**523 rev2y ago](https://www.amazon.com/dp/B0CZ8DJP5F) [**driamor 8 Pack Filter Cartridges Compatible with EF-S Element and BF5 BETTAFLO Filter Thickened Fish Tank Replacement Filters Cartridge with Zeolite**driamor**$8.10**346 rev3y ago](https://www.amazon.com/dp/B0CB3Q916W) [**HiTauing 8 Pack EF-S Filter Cartridges for EF-S Element and BF5 BETTAFLO**HiTauing**$8.69**3,205 rev3y ago](https://www.amazon.com/dp/B0B9656RGN)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**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**$7.24**4.1★**▲ 116%**](https://www.amazon.com/dp/B0GJ768YK9) [**driamor 8 Pack Filter Cartridges Compatible with EF-S Element and BF5 BETTAFLO Filter Thickened Fish Tank Replacement Filters Cartridge with Zeolite**driamor**$8.10**4.4★**▲ 71%**](https://www.amazon.com/dp/B0CB3Q916W) [**Top Fin EF-S Element Filter Cartridges (6 Count) for Fish Tank**Top Fin**$18.66**4.7★**▲ 38%**](https://www.amazon.com/dp/B08JJ3J41G) [**HiTauing 15 Packs Filter Cartridge for EF-S Element and BF5 BETTAFLO**HiTauing**$13.53**4.6★**— 6%**](https://www.amazon.com/dp/B0B967VBJW) [**HiTauing 8 Pack EF-S Filter Cartridges for EF-S Element and BF5 BETTAFLO**HiTauing**$8.69**4.6★**— 6%**](https://www.amazon.com/dp/B0B9656RGN)
**~~View all trending →~~**
## **What buyers say about top fin ef-s filter cartridges**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Value For Money**29%
*“Very affordable”*
**Size-Overall**21%
*“fits as it should”*
**Filtration**20%
*“Great filters”*
**Quality-Overall**7%
*“Good quality”*
**Ease Of Cleaning**7%
*“which stayed really clean”*
**Durability**3%
*“lasts a long time”*
**Advertised Vs Actual Product**3%
*“It does the job”*
**Ease Of Use**2%
*“They are super easy to use”*
**Water Flow**1%
*“Crystal Clear Water”*
**Water Resistance**1%
*“keeps water clear”*
### **What buyers complain about **
**Filtration**20%
*“NOT a quality filter”*
**Size-Overall**13%
*“Not correct size”*
**Quality-Overall**9%
*“NOT a quality filter”*
**Value For Money**7%
*“Expensive”*
**Smell**6%
*“failing to absorb odors or discoloration in the aquarium”*
**Ease Of Cleaning**6%
*“got as dirty as the name brand in half the time”*
**Compatibility-Overall**4%
*“Bad Fit for BF5”*
**Indigestion**4%
*“Caused Health Issues for My Betta”*
**Advertised Vs Actual Product**4%
*“Did not fit filter for Top Fin EF-S Element Filter Cartridge as described”*
**Water Resistance**2%
*“making the water murkier than before use”*
### **Top return reasons **
**Size-Overall**82%
**Filtration**7%
**Compatibility-Overall**4%
**Advertised Vs Actual Product**4%
**Value For Money**1%
**Functionality-Overall**1%
**Defective Material/Parts**1%
**Product Condition**0%
**Quality-Overall**0%
**Certifications**0%
## **Common questions**
- **Is top fin ef-s filter cartridges profitable to sell on Amazon United States?**
- The niche generates $110K/yr across 9 tracked products. 0 of 1 products launched in the last 360 days are still selling. 90-day search growth is -4.5%. Flapen's verdict: Skip it (37/100).
- **How competitive is the top fin ef-s filter cartridges niche?**
- 5 brands and 48 sellers compete. The top 5 products take 84% of clicks and top 5 brands hold 100% of demand.
- **What do buyers complain about in top fin ef-s filter cartridges?**
- Top complaints mined from reviews: Filtration, Size-Overall, Quality-Overall. The return rate is 1.8%.
- **When does demand for top fin ef-s filter cartridges peak?**
- Demand peaks in Jan–Nov; the busiest month runs 1.9× the quietest.
- **What does it cost to enter the top fin ef-s filter cartridges niche?**
- Listings span $7.24–$18.66; the average listing price is $11.00 (sweet spot $15–$100). The average incumbent carries 1,275 reviews — the moat a new listing must climb.
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