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Home » Brands » All Brands » Penn-Plax » Penn-Plax Ammonia-X Undergravel Filter Cartridge 2pk. #AX-2
Penn-Plax Ammonia-X Undergravel Filter Cartridge 2pk. #AX-2

Penn-Plax Ammonia-X Undergravel Filter Cartridge 2pk. #AX-2

Item #: 030172399510
Reg: $4.59
Sale: $3.80
You Save: $0.79 (17%)
  • Description
  • Reviews
Penn-Plax Ammonia-X Ammonia-Removing Undergravel Filter Cartridge is designed to fits Penn-Plax "Multi-Pore" and Undergravel "e" filters. Top quality zeolites eliminate the #1 fish killer - ammonia. Cuts down disease problems, solves over feeding, over crowding and foul water conditions. Contains 2 replacement cartridges.


  • Specifically designed to fit Penn-Plax "Multi-Pore", Undergravel “e” Filters, and Premium CFU Undergravel Filters
  • Easily slips into filter spouts with no need to disturb set-up
  • Cartridges should be replaced every 2-4 weeks
  • Keep your tank looking crystal clear
  • Quick, easy, disposable
  • For complete filtration, alternate with FC2 Carbon Filter Cartridges
Review Summary
4 Reviews
75% (3)
25% (1)
0% (0)
0% (0)
0% (0)
100% Recommend this product (4 of 4 responses)
By Plecky's D.
A Must Purchase For Ammonia Control!
February 4, 2022
We have a 14-year-old Plecostomus who has grown to 17 inches long, and anyone who has had this family of fish knows that they produce a good amount of ammonia to be offset... This product helps with the fight to keep readings under control :-) Charcoal is somewhat helpful in filters, but this gives you one more tool to keep your fish safe!
easy changing cartages :-) might not be fully effective for length of time advertised :-(
By Daniel W.
Ammonia levels lower
August 20, 2018
Undergravel cartridge that works
By judith m.
Columbus, ohio
penn-plax ammonia-x undergravel filter cartridge 2pk. #AX-2
October 11, 2012
I really needed them and shall need more1
I need them for my tank nothing
By Mary D.
Boone Iowa
These filters are hard to find in our area. Glad you sell them!
July 16, 2011
headline tells the story...
Fits our Undertow filter