Tetra Prefilter FK3 Replacement Cylinder Foam Media Filter

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About This Item

Details

  • Helps keep filter working efficiently
  • Keeps water clean and clear
  • Replacement for current filtration
  • For use in ponds and water gardens
  • Change regularly for optimum results
Learn More About Tetra From Our Team of Experts

Questions & Answers

3 Customer Questions


is this for a KOI BACKYARD pond? i have a filter on this currently and it looks similar but I can't tell how big this one is...

Answer by ChewyOct 11, 2017
It measures 5 3/4 inches in length and 4 inches in diameter and is idea for ponds and water gardens.

Can this just be cleaned as reused?

Answer by ChewyAug 31, 2018
It is recommended to change this filter regularly for optimum results. Reusing filters is not recommended as it can slow down filtration.

Will this work on an aquaclear 110 intake tube?

Answer by ChewySep 04, 2019
This replacement foam measures 6" length by 4" diameter with a 1" diameter hole in center and is for sue with the Tetra Water Garden Pump Pre-Filter.
4.6
Rated 4.6 out of 5 stars
29 Ratings

16 Customer Reviews



Rated 5 out of 5 stars
By SUSAN on May 15, 2025

Easier to change than the box filters

I need to clean my pond filters daily at this time of year. I find these to be the easiest to change out. Changing the filter takes less than a couple of minutes

I need to clean my pond filters daily at this time of year. I find these to be the easiest to change out. Changing the filter takes less than a couple of minutes. I keep a supply of spare filters handy at all times and hose the muck out of the used filters in a batch when it's convenient.


Rated 1 out of 5 stars
By Aleigha on May 13, 2024

doesn’t fit

Didn’t work the way I wanted and didn’t fit the right way

Didn’t work the way I wanted and didn’t fit the right way


Rated 5 out of 5 stars
By Janet on Apr 25, 2024

Everything great from phone call to order to filtering! Thank you

Everything great from phone call to order to filtering! Thank you


Rated 5 out of 5 stars
By takenbyaking12 on Aug 18, 2023

messy turtles

Exactly what I needed I have a top fin pro hob canister this fits perfectly on. I have a turtle this thick course material is much larger than the one that comes

Exactly what I needed I have a top fin pro hob canister this fits perfectly on. I have a turtle this thick course material is much larger than the one that comes with the top fin filter but works 10 times better ! It came in 2 days!


Rated 5 out of 5 stars
By Pondowner on Apr 28, 2022

Works great!

These are coarse, hard sponges with large holes. They work great for ponds. Chewy sells them at a great price and I don't know where to get them anywhere else. Highly

These are coarse, hard sponges with large holes. They work great for ponds. Chewy sells them at a great price and I don't know where to get them anywhere else. Highly recommend!


Rated 5 out of 5 stars
By janet on Aug 8, 2022

GREAT PRODUCT

Works very well with our filter system in our pond

Works very well with our filter system in our pond


Rated 5 out of 5 stars
By HP2026 on Dec 10, 2021

Multiple uses for your Aquarium

This can be used as a sponge prefilter for you HOB or it can be used as a replacement sponge for your air driven sponge filter. Because it has about a 20 PPI porosity,

This can be used as a sponge prefilter for you HOB or it can be used as a replacement sponge for your air driven sponge filter. Because it has about a 20 PPI porosity, it won't clog quickly like most sponge filter. I use it for both instances and it is fantastic and very inexpensive when you buy it from Chewy.


Rated 5 out of 5 stars
By FishyBusiness on Jul 31, 2021

Tetra prefilter for mag drive pump

These filters work great...The whole goes all the way through unlike the one that comes with the pump.The inlet part that holds it on is caped at the end ,so nothing

These filters work great...The whole goes all the way through unlike the one that comes with the pump.The inlet part that holds it on is caped at the end ,so nothing will get into the pump even though the hole goes all the way through the filter....I recommend these filters..they work well,and are very affordable.


Rated 5 out of 5 stars
By Reina on Jul 10, 2020

Tetra Prefilter FK3 Replacement Cylinder Foam Media Filter

Filters are wider than thought but, works great pond is nice and clear and fish are happy.

Filters are wider than thought but, works great pond is nice and clear and fish are happy.


Rated 5 out of 5 stars
By Wendy on Oct 25, 2019

Great product that fits on most pumps!

Great product! I’m currently using on 2 different pumps and only need to change them out every 4 days for a turtle pond! Definitely recommend this product. Very

Great product! I’m currently using on 2 different pumps and only need to change them out every 4 days for a turtle pond! Definitely recommend this product. Very happy customer.