Slim Aquarium Filter, Quiet Fish Tank HOB Filters for up to 5 Gallon Aquariums, Adjustable Flow, 42 GPH, 3W

This filter works perfect for a little Top Fin 3 gallon tank. I have a small tank set up for Corydora fry and needed a decent filter with an intake pipe. The filter that came with the aqaurium was trash, and I did not like it. It pulled from the bottom and kept sucking fry up. The first replacement filter that I got did not have a place for carbon or any type of sponge. This one is seriously perfect. It has a carbon cartridge with a sponge and also a sponge filter for the intake. It helps pre-filter AND keeps from sucking anyone up. The replacement cartridges are not expensive (6 for $9.99 or 12 for $14.99). It is very easy to clean and does not make any splashing sounds. It has a big enough area to add your own media, if needed. The carbon keeps everything circulating to avoid any funky smells. *I just put it in before taking photos, so the tank is not the cleanest.

This will be my go to HOB for 1-5 gallon and my first choice for a 10 gallon betta set up. I have two top fin 5 gallon tanks that I bought in an emergency situation. The filters they came with were intrusive, they hung inside the tank, and were garbage at their intended function. After about 6 months of dealing with them I searched for a replacement that would fit and work. The lids that came on the top fin tanks had a cut out for the filters so I needed something that would allow the lid to fit because we have a cat. After a couple hours of research and with cost in mind I chose these. And I’m extremely happy. They are very quiet, do the job they are suppose to and look good doing it. The flow adjustment is responsive and the design of the flow knob is easily serviceable. In my opinion with weekly water changes they are perfect for heavily stocked 1-5 gallons and may even be used for something like a 10 gallon planted betta home with light flow.

It's reasonably quiet with a good flow rate, but you'll probably want a baffle for something like a betta. Took about five minutes to put together and seems to be working well. I replaced the cartridge with filter floss since it's for a hospital tank and the activated charcoal in the cartridge would absorb any medication I need to use.

This is a strong, well-built little filter. For most tanks, I think it would be well worth the money. I have a very shallow watercress tank with a sand substrate and soil underneath, and this filter worked well at first. In fact, I bought the first one on March 10, 2026, and liked it so much that I bought a second one for my other watercress tank on March 19, 2026. Unfortunately, they both eventually started clogging daily because of the sand. I put a bit of slate over the sand to act as a baffle, under the intake and outflow, which helped them keep chugging along for another week. I think that these would be great if I had pebbles on top of the sand, or even gravel, but then that would impede my watercresses' ability to spread and turn into a delicious mat of salady goodness. RIP NICREW, you were great while you lasted.

This filter is awesome. I needed something that took up less room in my 5 gallon, so I gave this one a chance. It works really well, is super quiet, and it’s very easy to change the water flow for your needs. It is great for custom filter media as well.

UPDATED REVIEW: We got this to go on a 2 Gallon Thrift Store tank we will use to house 'culled' Neo Shrimp. Tank is 6"x12"x7"H and this filter moves the water well. I had to notch the solid acrylic lid and nip just a touch off the plastic tank rim for a perfect fit but hey.... I added a shot w/ my hand in it for scale...this is a SMALL, noiseless Filter! OK yes you do need to fill it first... but come on.... scoop up a cup of water from the tank and you are good to go. And after plugging it in it took about 30 seconds to self-prime... oh no! Try priming a 15 Gallon external filter sometimes......LOL! All in all a great little addition to our growing collection of micro-nano tanks. ------------------------------------------------------------------------------ UPDATE On 10/10, after a tank move, the filter stopped working correctly. This was after less than 3 months and outside the Amazon Return Window. I contacted Nicrew that evening by email and received a reply by morning. They expressed their concern, suggested some fixes and told me not to worry as it had a one year warranty. As per their request I sent a video of the pump as it faltered and froze up. They said they would send me a replacement. Three days later I received a replacement pump via Amazon!! New pump was up and running in minutes! OUTSTANDING CUSTOMER SERVICE!!!

I really love how quiet this filter is. And it gives just the right amount waterflow for my two and a half gallon nano tank. The first one I purchased lasted for a year. When it died, I repurchased a new one that only lasted four months. It died just after the amazon return window. I thought maybe I got a dud, so I went ahead and ordered a replacement. The replacement died after four days. I'm not sure how to feel about this filter anymore.

Quiet & Low Profile – Perfect for Nano Tanks! ⭐⭐⭐⭐⭐ ​I’m really happy with this NICREW Slim Filter. If you’re looking for something that won’t take up half the tank space, this is it. The profile is incredibly thin, which keeps the focus on the fish and plants rather than a bulky piece of equipment hanging off the back. 🌿🐠 ​The best features: ​Truly Quiet: Living up to the name—once it’s primed, it’s practically silent. I have this in a room where noise matters, and I barely notice it’s running. 🤫 ​Adjustable Flow: This is a life-saver for smaller tanks or fish like Bettas that don't like a heavy current. You can dial it down to a gentle trickle without any motor strain. 💧 ​Small Footprint: It fits perfectly on rimless or standard small tanks without looking clunky. ​For a budget-friendly filter, the build quality and performance are top-notch. It’s effective, easy to maintain, and keeps the water crystal clear. Highly recommended for any 1–5 gallon setup! ⭐⭐⭐⭐⭐

Works perfect. Very quiet and easy to assemble. Perfect for my small tank.

This product is one of the worst products I have bought. If you need my evaluation, I will give it a bad evaluation because it broke down in the first week and when I started using the product, it was very hot. I do not advise people to buy it and I advise them to buy any other product.

Extremely quiet and discreet design, very conveniently sized. Run it on my shrimp-only 20l tank and bought it mostly for surface agitation but surprised at how good the filtration actually is for such a compact device. Well priced too! Will definitely use again.

great filter, not to loud or quiet! It’s small and compact so easy to hide in tank.

Stopped working in the first 3 hours of use