Penn-Plax Small World Replacement Aquarium Filter Media (2 Pack) – Safe for Freshwater and Saltwater Setups, SWF1C

Good product, good price

I really like these little filters. They are a good deal and very easy to change out when dirty. I have a small 6 gallon planted tank with some little critters and this filter does the trick.

They're perfect for beta tanks

I uploaded a video so you can see the size and hear the pump.When we first won two goldfish for our two boys at a fair, we bought the bowl and rocks, but no filter. A week later, one of the fish died, even though I have been changing the water with filtered water.Now that we have this filter, the fish have been very healthy and the water much clearer.I still change the water out each weekend, and wash the rocks and inside of the bowl because it gets pretty slimy. So far the fish seem to be really happy.The main con is the pump is a little noisy, hence four stars.Below is the review of the replacement filter.When I ordered a Filter replacement, I got the wrong product:I needed the SWF-1C rectangular cartridge but I ordered from ToysNGames and received the SWF2C cylindrical instead.I highly recommend this for a small 2 gallon fishbowl to help keep the water clear instead of having your fish swim in stagnant water.Each time I switch out the water, I have to rinse the filter case as well since there is a layer of slime? The white filter part turned tan after about 3 weeks.I change the water with carbon filtered water every week and add some water treatment.So far, my comet goldfish has been pretty happy.Again, the correct replacement filter needed is the SWF-1C

This is an absolute must if you are using an air pump to filter your small tank. The cartridge have bio media/carbon and a sponge, and these are essential components for keeping "good bacteria" in your tank, besides being able to filter and oxygenate the water.Personally, I do not replace the cartridges often. What I have done is cut the base of the cartridge so I can take the sponge out and rinse it (make sure you do this in a little container with aquarium water). Then I put it back in the cartridge. That way I can keep the sponge clean and the bacteria that allows the tank to be cycled (and save money). Alternatively, cutting the bottom will give you the opportunity to upgrade the media and sponge of your choice (see picture).I would suggest using an adjustable valve to control the air going into the filter, so you can increase or decrease the amount of bubbles (the filter is a bit noisy, but is just the nature of any box filter design). I've had great experience and results with this product in my 5.5 gallon Betta tank.

Despite knowing these are amazing filters, something in my head still tells me that a more expensive or electric filter is better. For a tank on the smaller side there really isn't a better choice. Ideal for my bettas. Doesn't hinder their swimming in any way, but keeps the water healthy and clean. I use one cartridge for 4-6 weeks, rinsing any solid debris in the water taken from their tanks in a weekly water change. Rinsing the dust and saturating the sponge of a new cartridge in the old water from a cleaning. The casing is surprisingly more durable than it looks, I know because occasionally I take the sponge from a used cartridge out to cycle a new tank and it takes some work. I really can't speak highly enough of these filters

I love Bettas so needless to say my sister wasn't very big, only two and a half gallon hexagon to be exact but this is the filter I always used for the years that I've had Bettas. Unfortunately pet stores in my area no longer sell them. I tried another filtration system and wasn't happy with it so decided to start buying replacement filters here on Amazon. I bought them multiple times here and would continue to do so if my Betta did not die. I just decided it's time to pass my fish tank on the someone else. My Betta's always lived a long time- my last having lived for 3 years and I attribute it to the filter.

I’ve used these before and am very satisfied with their durability and ease of use.

Perfect replacement cartridges for my little Small World filter which I'm using in a 12ltr tank reserved for baby Platies! 🐟 Unfortunately these cartridges don't come apart, so you can't prolong the life of them by rinsing the interior sponges out in tank water, making them pretty expensive seeing as they need changing every 2/3 weeks, but at least they come in a two-pack so there's a spare for the next change-over. Easy to click in and genuine Small World filter media 🙂

Great for what it is, not quite what I required!

Gr8 4 small tanks

If you do not have a adjustable check valve the pressure from these filters will be very strong but the filter does it’s job well with regular siphoning, without siphoning filter gets dirty very quick and will have to change the cartridge before 4-6 weeks as it specifies.

These are great and very easy to use, it works out cheaper than buying them individually. If you're new to this, these are just the replacement filter cartridges and you need to also buy the Small World pump to use with it. I usually need to change the filter every two weeks.