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

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!

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

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.