Finnex Carbon Filter Cartridge Pad, Nano Filter, Fits PF-7 and PF-5, 6 Pack

I'm very pleased with this nano filter. It does not rattle, is truly adjustable and is still working after my negligence in letting it run dry a few times. I've used it for fish who prefer low flow and for fish where I have not used an air stone but instead used this filter to provide surface agitation. I think this filter is a great versatile tool for aquariums up to 20 gallons. It's also an added bonus that a pre-filter sponge is included. I recently browsed similar models and noticed that many did not include the pre-filter sponge. I prefer this over a sponge filter because it takes up so little space in the aquarium and can adjust to suit the needs of the tank inhabitants.

I use this little filter on a 2.5USG plant grow out aquarium -- growing out plants as well as Endlers Livebearer fry & snails. Set on minimum flow with modified media (not using the cartridges available for the filter).... Have the little thing doing every aspect of filtration with heavy concentration on biological....Here's my setup for crystal clear water:• Main filter box has a layer of crushed lava rocks -- about half pea size --• A coarse sponge layer (15ppi) on top, .3" thick• A finer sponge layer (30ppi) over that, .5" thick• 2 layers of 2 diff't types of chemical media wrapped in poly-fiber• Topped off with another bit of coarse sponge• The outflow has a bit of bonded (blue/white) media & a thin layer of coarse sponge• The intake box also has a 30ppi section of sponge at the back and smaller sections of 15ppi along the sides.• The bottom of the uplift/intake tube is encase in a coarse sponge (15ppi) sleeve which acts as a pre-filter to keep plant matter out of the filter (and available to snails), but also protects the young fish and snailsWith the above formula + live plants, the little aquarium doesn't even require regular water changes for parameters to stay perfect & the water clear.... Only time there is any water change is when fish or plants need to be pulled out for sale or to be moved into a diff't aquarium. The chemical media gets changed out every 5-6 months or when flow rate shows a need for the bio-media to be rinsed. The pre-filter does need to be cleaned up a bit more often, but that's only because the tank is used for growing out plant clippings from plants with fine leaves that get into the water column.As for noise level.... The filter is fairly quite; one of THE quietest I've used at this size .... There is a low, constant hum from the motor which is amplified by the glass aquarium, so I put a bit of noise deadening, thin foam between the motor housing and the glass.... The cover also doesn't lock into place, so it can rattle from the motor's vibration --- I remedied that with a couple of small, but heavy, decorative rocks in just the right spots.As far as suitability.... A lot of folks like to get these little filters for Bettas..... So, I will address that.... For a Betta, 52gph is suited for 5-7 USG aquariums. It's not as simple as just the gph, however.... This filter isn't suited for small spaces where the flow gets turned back around too quickly as that amplifies the flow rate too much for a Betta -- bowls and vases, for example.Some noted the minimum tank line being of concern for rimless tanks or waterfall creation..... I think ppl are misunderstanding what that minimum water line actually means.... It's the minimum water level for starting the filter, not for it's continuous operation..... Once the filter is started and running, the minimum water line is actually the first joint on the uplift tube, so water can be lowered once the filter has reached stability (not spitting out water bubbles). The uplift tube joint sits about 3 inches below the minimum water line on the filter box itself. That makes this little filter suitable for creating little water falls or keeping the water level down a bit for fish that like stronger currents. This filter is NOT suitable for high bioload fish of any kind.I'd have no reservations in recommending this little filter for light bio-load aquariums from 3-8 USG. For seasoned, knowledgeable aquarists/hobbyists, the filter is surprisingly customizable -- can even make for a highly effective 100% bio-filter.

The flow is gentle for 2.5gallons I am using for medicating fish, most filters are too strong and stress fish in tiny spaces but this one is gentle. It fits too because it's external, easy to install, just hang it from side of tank. Doesn't break easily either, works a while.

Really good for the price.I use these on 10 gallon aquariums in addition to a large sponge filter. It creates a nice flow and is easy to swap out media for something different. If your media gets clogged it will sometimes drip out of the one corner onto your floor - easy to prevent as long as you check your media every so often.If your power goes off it will keep enough water on the impeller to start again (a complaint i have with some more expensive HOB filters.Dont use if you have duckweed or at least use some sort of divider because it is small it drops water very close to the inlet which will pull some duckweed down and clog the intake strainer.

I like this little filter system. I have it in a medium size tank and it works well keeps the water flowing

I was super excited for this filter for my tank but a piece came broken so I had to return it. Build quality:Definitely room for improvement but i loved the look of it.

This is a very small outside power filter. While I am not familiar with the brand, it has a solid build to it. Its no different than a mfg like Hagen. It is designed for small aquariums - it is listed (when running optimally) @ 52 gallons per hour. This filter is purely for mechanical filtration as it uses a sponge and small cartridge. There is no room for any filter media to enhance the growth of bacteria. We have it a aqueon 3 gallon aquarium with a few goldfish. It replaced a 25 gph submersible filter as we were having chronic problems with cloudy water. I don't care what the mfg says, I wouldn't use it above a 5.5 gallon aquarium or so. You really cannot beat it - especially at this price point.

This filter worked very well in my aquarium. It was easy to install. It was easy to clean and has good storage capacity for waste filtration. A good, durable solution for keeping the aquarium water clean for my fish pets.