Penn-Plax Undergravel Aquarium Filter for 40-55 Gallon Tanks – 4 11.25” x 11.25” Plates – Beneath Gravel System for Clear, Clear Water – Protected for Freshwater and Saltwater Tanks (CFU55)
$26.44
Value: $26.44
(as of Mar 25, 2025 04:22:06 UTC – Particulars)
PENN-PLAX presents the Clear-Free Premium Beneath Gravel Aquarium Filter.
Those that’ve been across the aquatic block for some time
know that Beneath Gravel Filters (UGFs) are a testomony of time.
This Filter is air pushed and makes use of an Air Pump (not included) to cycle crystal clear water all through your aquarium,
whereas maintaining a crisp and neat look inside.
This implies there’s much less “shifting components,” making for simplistic and simple upkeep.
It’s appropriate for best suited for many 40 – 55 gallon aquariums, and is protected for Freshwater and Saltwater setups.Organic, Chemical, and Bodily Filtration:
As air is pushed by way of the Air Stones and rises by way of the Elevate Tubes,
water is gently suctioned by way of gravel and the filter plates,
permitting each air and water to go by way of the Filt-a-Carb Activated Carbon Cartridges.
When water continues to be drawn by way of, anaerobic micro organism collects and colonizes throughout the gravel and filter plates.Additionally Aerates Your Tank:
Because the Clear-Free Premium Beneath Gravel Filter is air pushed
by way of using Air Stones and an Air Pump (not included), it additionally aerates your tank.
In essence, your aquarium is being filtered and aerated on the similar time, although the identical system!
It’s a filter and bubbler in 1!Objects Included:
The Clear-Free Premium Beneath Gravel Filter consists of
4 Filter Plates
4 Adjustable Elevate Tubes
4 Straight Airline Tubes
9 Filter Plate Connecters
4 Replaceable Filt-a-Carb Activated Carbon Media CartridgesMeasurements:
Every Filter Plate Individually = 11.25” (W) x 11.25” (D)
Filter Plates Collectively = 45” (W) x 11.25” (D)
Every Elevate Tube at Filter Plate Base = 13.25” – 16.5”Store PENN-PLAX for All Your Pet’s Wants:
PENN-PLAX is a producer and distributor of high quality pet provides,
who concentrate on creating wonderful pet merchandise for animals, each nice and small.
Is Discontinued By Producer : No
Product Dimensions : 11.5 x 2.5 x 11.5 inches; 2.02 Kilos
Merchandise mannequin quantity : CFU55
Date First Obtainable : July 6, 2010
Producer : Penn Plax, INC.
ASIN : B003UTNOU6
Nation of Origin : China
NOTHING LIKE OLD SCHOOL: The Clear-Free Premium Beneath Gravel Filter is air pushed and makes use of an Air Pump (not included) to cycle crystal clear water all through your aquarium, whereas maintaining a crisp and neat look inside. This implies there’s much less “shifting components,” making for simplistic and simple upkeep. This filter is appropriate for many 40 – 55 gallon aquariums.
BIOLOGICAL, CHEMICAL, AND PHYSICAL FILTRATION: As air is pushed by way of the Air Stones and rises by way of the Elevate Tubes, water is gently suctioned by way of gravel and the filter plates, permitting each air and water to go by way of the Filt-a-Carb Activated Carbon Cartridges. When water continues to be drawn by way of, anaerobic micro organism collects and colonizes throughout the gravel and filter plates.
ALSO AERATES YOUR TANK: Because the Clear-Free Premium Beneath Gravel Filter is air pushed by way of using Air Stones and an Air Pump (not included), it additionally aerates your tank. In essence, your aquarium is being filtered and aerated on the similar time, although the identical system. It’s a filter and bubbler in 1.
ITEMS INCLUDED: The Clear-Free Premium Beneath Gravel Filter consists of 4 Filter Plates, 4 Adjustable Elevate Tubes, 4 Straight Airline Tubes, 9 Filter Plate Connecters, and 4 Replaceable Filt-a-Carb Activated Carbon Media Cartridges.
MEASUREMENTS: Every Filter Plate Individually = 11.25” (W) x 11.25” (D) / Filter Plates Collectively = 45” (W) x 11.25” (D) / Every Elevate Tube at Filter Plate Base = 13.25” – 16.5”
Clients say
Clients discover the pet provides simple to arrange and use. They recognize the nice filter high quality and worth for cash. Nonetheless, some clients have points with the tube high quality and construct high quality. General, opinions on tank cleanliness and match differ.
13 reviews for Penn-Plax Undergravel Aquarium Filter for 40-55 Gallon Tanks – 4 11.25” x 11.25” Plates – Beneath Gravel System for Clear, Clear Water – Protected for Freshwater and Saltwater Tanks (CFU55)
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$26.44
Wendy Cook –
Works great!
We bought these to put in our 75 gallon tank so that our fancy goldfish had extra filtration. We already use a canister filter for them but I had an extra air pump from when I got an under gravel added on to my 55 tropical tank (because I’d accidentally ordered 2). I use this same brand in that one, as well!The price is awesome and they work amazingly. Helps keep the water oxygenated and they fit perfectly. Once you get your gravel or substrate in you don’t even notice them.Also, these don’t make noise: whatever noise you hear comes from your air pump, and if the air is too strong or you have a crappy pump, then yes, they’re loud-but do it right, with air line adjustable knobs and a good quality pump and you’ll have no problem. The lines were great and they gave plenty with the set up to get it up and running! Will be back to buy another one soon since I’m setting up a 3rd tank soon!
Nelson B. –
A must have
I’ve done aquariums for 40 years and have found these very useful. As long as you care and maintain your aquarium I’ve never had to pull it up and clean it out.
William J Groves IV –
better than canister filter
they work great
Lisa KH –
Must Buy for Fresh Water Aquariums
I would have given 5 stars, but my first order was damaged, i.e., the heads and tubes were cracked. I sealed the cracks, so it is functional. I would have returned it or called Penn-Plax customer service to resolve but I needed to get the aquarium set up for my fry so I didn’t have time to wait. However – I ordered a 2nd set for another tank and there were no cracks or defects of any kind. The product was wrapped in heavy duty bubble wrap so I’m assuming there may have been previous delivery production issues because the first order was not wrapped in bubble wrap. I’m probably not the only customer that received damaged tubes.
Maggotaux –
Let me explain the rating.
This item claims to be for a 40/55 gallon tank. Wrong. I’m not sure what 55 gallon tank these guys could possibly work in. But I have 7 inches of space that should have easily 5 inches of height left to fill. The tubes are not meant for a 55gallon tank. Refer to my picture’s. I’m not upset with the product but even the screens fell short of about 10 inches all the way across the front. The product was easy to assemble and came neatly packaged. This is not a seller issue. The seller sent and sold the item based off the manufacturer’s packaging using that as reference for the sale. If you have a 55 gallon tank. Measure it and go to a local pet store that specializes in selling aquatic products and get the right product for your tank.I will have to go and purchase extra tubes, measure, cut and connect them now to achieve the proper height. I will also have to not be reliant on the short screens and have to weekly clean the river rock that will lay directly on the glass.Extra work to make it work, extra work to keep it clean, extra money spent. Not happy with the purchase as there needs to be proper measurements for the plastic floor screens so other people aren’t having this issue. Other than that. The product will definitely do the job it was made to do. But not full scale for a 55 gallon tank.
Ravanja –
Great filter
Well made under gravel filter. I used it in a 40 Gallon tank I’m just starting to set up. I used three of the four supplied bases and my tank is 36 inches long. Everything was there taped up. The plastic is perfectly adequate for the job. There is no need to go heavy duty on these parts. They will last decades as is which is more than can be said for the HOB filter variety. Just getting back into the hobby and I learned my lesson well when the HOB filters became the preferred profit makers for filter companies years ago.Once a very popular filter, actually it was considered the best at the time, it is now frowned upon and is no longer considered the best filter to use. This is not because the filter is not great at what it does, its just that the definition of “best” has been refined for modern times. “Best” is now defined by a product that requires regular purchase of filter media to get the “best” profits for companies producing them. They are also “best” at wasting resources and adding to landfills. They are also “best” at unreliability being at about five years or so.So if you want the “best” available today in terms of all those things, don’t get this.This filter won’t create waste for land fill, won’t fail spectacularly, won’t require you to keep the filter companies profits afloat, but it will filter your aquarium crystal clear for decades without issues or monthly costs. Just understand how they are meant to be maintained (leave them alone!) and you are good to go.
Rick Montague –
Just what i needed
Works great
CrazyJay808 –
Fair price for the the quality.
Delivered as described. Quick ship. Fair price for the the quality. Would purchase from again.
Kyle –
I bought this for one of my 75 gallons as a test because this item is so inexpensive.So far working great. I have canister filters, sponge, and hang on the backs. For some reason this under gravel filter makes the water look the most clear. I believe benefits bacteria will thrive because of the huge surface area.PROS: very clear water. Handles debris just as effectively as other filters. Air atone works really good. Good for plants as waste is held under gravel for plant roots to maximize on.CONS: have to pretty much dismantle the tank to set it up. Parts seem a little cheaply made, but not too bad, and I must say they are all working fine and haven’t given my any issues.
Me –
Great quality product. Easy to use and very functional…Makes using an aquarium plenum a pleasure.
Thomas Daniel –
Good
Arleta Wirtz –
👍
Yevgeniy –
The “filtration” device operates for a very limited amount of time. The concept is excellent – water passing through the aquarium substrate is cleaned mechanically, etc. However, in reality, the aquarium substrate gets covered with silt deposits over time, and this design will no longer be able to perform its primary function. The only way to address this is to siphon the substrate during each aquarium cleaning, which is recommended but does not guarantee the continued operation of the device.