---
title: "Top Fin Rf-l Filter Cartridges — $12K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/pet-supplies/top-fin-rf-l-filter-cartridges"
last_updated: "2026-07-21T17:41:01.994Z"
locale: en
meta:
description: "Niche score 38/100 · $12K/yr market · 3K searches/yr · $15.83 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 38/100 · $12K/yr market · 3K searches/yr · $15.83 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Top Fin Rf-l Filter Cartridges — $12K/yr Amazon US Niche (2026) - Flapen"
---
# **top fin rf-l filter cartridges**
**Skip it**
Brand-locked demand (top 5 brands take 100% of clicks) — this niche doesn't clear our bar today.
Market size 3Growth 40Conversion 100Competition 3Returns 77Price range 68Avg price 77Brand share 0Review moat 84Quality gap 22
**Conversion**
**Incredible****24.4%**
search→purchase rate — share of searches ending in a sale
**Review moat**
**Great****327.17**
avg incumbent reviews — the moat a new listing must climb
**Returns**
**Great****1.9%**
return rate — above 6% kills the launch gate
**Avg price**
**Great****$15.83**
avg listing price — sweet spot $15–$100
**Price range**
**Good****$12.86–$19.59**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Growth**
**Okay****+11.8%**
90-day search growth — must beat 0% to launch
**Quality gap**
**Bad****4.7★**
avg incumbent rating — lower means beatable quality
**Market size**
**Bad****$12K**
$12K/yr · 3K searches
**Competition**
**Bad****97%**
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 rf-l filter cartridges is a $12K/yr Amazon United States market (3K searches/yr). The top 5 brands hold 100% of demand. Demand peaks in Jul–Aug. Verdict: Skip it — 38/100.
Data updated Jul 17, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **top fin rf-l filter cartridges market data**
- **Units sold / yr**
- **750–1K**
- avg 0–100/product
- **Revenue / yr**
- **$12K–$16K**
- units × avg price
- **Launch success**
- **—**
- 0 of 1 new (360d)
- **Conversion rate**
- **24.4%**
- **Avg BSR**
- **#545**
- **Page quality**
- **0%**
- **Prime**
- **100%**
- **Sponsored**
- **67%**
- **Out of stock**
- **0.0%**
- **Avg brand age**
- **20 months**
- **Avg seller age**
- **128 days**
## **Competition & brand share**
The top 5 products capture 97% of clicks — a locked-up shelf that new listings rarely crack.
**Brands**
**5 **▼falling
**Sellers**
**33**
**Top-5 brand share**
**100%**
Top 20: 100%
**Top-5 click share**
**97%**
Top 20: 100%
**Open market**
**0%**
- Switior68% - Top Fin12% - Czarixa11% - Yoolight6% - SAMANIJA3% - Open — no brand owns it (0%)
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — +11.8% search growth over the last 90 days.
175125Spike '25Prime Day '25Black Friday '25Holiday '25Spike '26Prime Day '26 seasonSepDecMarJunAugNovMarMay
Peak months: Jul, Aug · busiest ÷ quietest = 1.7×
[**Open Trend **](https://flapen.com/research/us/pet-supplies/top-fin-rf-l-filter-cartridges/trend)
## **Top top fin rf-l 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%$2K30%$4K45%$5K60%$7K1101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 6 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Switior 8 Pack Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$15.63**4.7★217 rev](https://www.amazon.com/dp/B0DKX88PWY) [2**Switior 12 Pack Large Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$18.38**4.7★217 rev](https://www.amazon.com/dp/B0DKXPPGF4) [3**Top Fin Retreat Filter Large RF-L (6 Count)**Top Fin**$19.59**4.7★1,377 rev](https://www.amazon.com/dp/B07V2T7Y35) [4**Czarixa 8 Pcs RF-L Fish Tank Filter Cartridges for Topfin L Retreat Filters Aquarium Replacement Large Filter Cartridge with Carbon Compatible with Top Fin Desktop Aquariums with Large Retreat Filter**Czarixa**$14.88**4.8★6 rev](https://www.amazon.com/dp/B0GFCMN1R3) [5**Yoolight 6 Pack RF-L Large Retreat Filter Cartridges Compatible with Aquarium Remplacement Aquarium Carbon Cartridge**Yoolight**$13.65**4.5★48 rev](https://www.amazon.com/dp/B0DG55QDWY)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**Czarixa 8 Pcs RF-L Fish Tank Filter Cartridges for Topfin L Retreat Filters Aquarium Replacement Large Filter Cartridge with Carbon Compatible with Top Fin Desktop Aquariums with Large Retreat Filter**Czarixa**$14.88**6 rev6mo ago](https://www.amazon.com/dp/B0GFCMN1R3) [**Switior 8 Pack Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$15.63**217 rev1y ago](https://www.amazon.com/dp/B0DKX88PWY) [**Switior 12 Pack Large Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$18.38**217 rev1y ago](https://www.amazon.com/dp/B0DKXPPGF4) [**Yoolight 6 Pack RF-L Large Retreat Filter Cartridges Compatible with Aquarium Remplacement Aquarium Carbon Cartridge**Yoolight**$13.65**48 rev1y ago](https://www.amazon.com/dp/B0DG55QDWY) [**SAMANIJA 6-Pack Fish Tank Aquarium Filters Replacement for Top Fin RF-L Large Retreat Filter Cartridges**SAMANIJA**$12.86**98 rev2y ago](https://www.amazon.com/dp/B0D22GVLVV)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**Czarixa 8 Pcs RF-L Fish Tank Filter Cartridges for Topfin L Retreat Filters Aquarium Replacement Large Filter Cartridge with Carbon Compatible with Top Fin Desktop Aquariums with Large Retreat Filter**Czarixa**$14.88**4.8★**▲ 105%**](https://www.amazon.com/dp/B0GFCMN1R3) [**Yoolight 6 Pack RF-L Large Retreat Filter Cartridges Compatible with Aquarium Remplacement Aquarium Carbon Cartridge**Yoolight**$13.65**4.5★**▲ 65%**](https://www.amazon.com/dp/B0DG55QDWY) [**Switior 12 Pack Large Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$18.38**4.7★**— 3%**](https://www.amazon.com/dp/B0DKXPPGF4) [**Switior 8 Pack Filter Cartridge for Top Fin RF-L Filter Aqurium Filter Cartridge Refill for Top Fin Desktop Aquariums with Large Retreat Filter**Switior**$15.63**4.7★**— 0%**](https://www.amazon.com/dp/B0DKX88PWY) [**Top Fin Retreat Filter Large RF-L (6 Count)**Top Fin**$19.59**4.7★**▼ 32%**](https://www.amazon.com/dp/B07V2T7Y35)
**~~View all trending →~~**
## **What buyers say about top fin rf-l filter cartridges**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Filtration**26%
*“These aquarium filters are quite good”*
**Advertised Vs Actual Product**21%
*“Works as expected”*
**Size-Overall**14%
*“Fits perfect on my aquarium setup and keeps it very clean, exactly same size as original and fits and works perfect”*
**Ease Of Cleaning**14%
*“Keeps tank clean”*
**Quality-Overall**7%
*“Same size and very good quality”*
**Value For Money**7%
*“Value for money”*
**Water Flow**5%
*“The water is very clear”*
### **What buyers complain about **
**Ease Of Cleaning**33%
*“It's like looking through a window pain after you have cleaned it”*
### **Top return reasons **
**Size-Overall**89%
**Filtration**6%
**Advertised Vs Actual Product**5%
**Compatibility-Overall**2%
**Functionality-Overall**1%
**Water Resistance**0%
## **Common questions**
- **Is top fin rf-l filter cartridges profitable to sell on Amazon United States?**
- The niche generates $12K/yr across 6 tracked products. 0 of 1 products launched in the last 360 days are still selling. 90-day search growth is +11.8%. Flapen's verdict: Skip it (38/100).
- **How competitive is the top fin rf-l filter cartridges niche?**
- 5 brands and 33 sellers compete. The top 5 products take 97% of clicks and top 5 brands hold 100% of demand.
- **What do buyers complain about in top fin rf-l filter cartridges?**
- Top complaints mined from reviews: Ease Of Cleaning. The return rate is 1.9%.
- **When does demand for top fin rf-l filter cartridges peak?**
- Demand peaks in Jul–Aug; the busiest month runs 1.7× the quietest.
- **What does it cost to enter the top fin rf-l filter cartridges niche?**
- Listings span $12.86–$19.59; the average listing price is $15.83 (sweet spot $15–$100). The average incumbent carries 327 reviews — the moat a new listing must climb.
## **Related niches in Pet Supplies**
- 73 [**phosphate test kit**](https://flapen.com/research/us/pet-supplies/phosphate-test-kit)$194K/yr+152.5%**Worth a look**- 73 [**flea repellent for dogs**](https://flapen.com/research/us/pet-supplies/flea-repellent-for-dogs)$1.7M/yr+136.7%**Launch it**- 73 [**kitten bottles for nursing**](https://flapen.com/research/us/pet-supplies/kitten-bottles-for-nursing)$457K/yr+166.2%**Worth a look**- 73 [**dog stake**](https://flapen.com/research/us/pet-supplies/dog-stake)$573K/yr+55.9%**Worth a look**- 73 [**bully sticks**](https://flapen.com/research/us/pet-supplies/bully-sticks)$12.4M/yr-6.9%**Worth a look**- 73 [**pet oral tartar remover spray**](https://flapen.com/research/us/pet-supplies/pet-oral-tartar-remover-spray)$100K/yr>1,000%**Worth a look**[**All Pet Supplies niches **](https://flapen.com/research/us/pet-supplies)