6-Layer Betta Corner Sponge Filter --- Underwater Corner Aquarium Filter - Works for Tropical Fish & Breeder Aquarium - Slow current - Perfect for Fry & Small Fish - Must-have for Aquarium Hobbyist

I really like this filter, but my Betta doesn't. I have considered taking it out because all Augustus (my Betta) does anymore is stare at my filter like it's his life-long mortal nemesis. He just lays against the side of the tank and watches it. Maybe he finds it soothing, I don't know. I started putting it on a timer so it won't be going at night and he can get some fish-sleep. Maybe he's cold?... I have a lot of concerns. Anyway, there's a chance that you could psychologically torment your fish with this product. Also, it doesn't explicitly say it, but you need tubing and an air stone to run this. All the instructions are in Japanese so allow me to instruct you: Assemble it like you see in the picture, and attach some tubing to the hole in the top (through the larger plastic tube), connect that tubing to an air-stone and plug it up. The air pressure is going to be really high, so be prepared to cut some careful holes in that tubing. Anyway, this was a long rant. The product works - my Betta's water is clean now and has been for weeks.

I had a Betta that was very picky about the filters I could use in the tank - too strong of a flow and he'd abandon half the tank for a corner. He loooved this sponge filter. I used a double valve connection for the air pump and manipulated how much air went through it. He actually plays in the bubbles! It's worth noting that a sponge filter doesn't keep the water as clear or odor free as a carbon filter does, but it's nothing standard weekly water changes can't compensate for.

I bought this back in the beginning of July for my 5 gal. Betta tank. Stocked with 1 Betta and 2 Plecos. Bought it because of a continuos brown algae problem. I had tried fungascide, a few different water conditioners, snails, weekly water changes, etc. Well, I do a complete water change every 2 weeks since buying this, and bleach all decor and gravel. I'm still having brown algae, and the tubing for this filter gets a thick white film that I have to continually cut off. There is no way to control the bubble output on this either. I'm not certain if I'm just not doing something correctly or this just isn't strong enough for my tank. Fyi, I bought the 2 Plecos a month ago to help with the algae, no change at all, just added to the "poop" in the tank 🤔😐😯

This fits perfectly in my betta's tank and cleans the water well. I took off one star for the fact that it takes some time to get it to stay at the bottom of the tank and not float freely. You have to jam the gravel (or whatever substrate you use) around the bottom to keep in place. The water appears clean and it only needs to be squeezed out during every water change to keep it flowing smoothly. I love how it not only filters, but adds oxygen to the betta tank.

My Betta loves this filter. I tried 3 other filters before this one and it’s the only one that didn’t have strong current. Which my fish didn’t like current. So it works perfect. All the reviews of it being hard to keep submerged is true. But after playing around with it I’ve been able to keep it down

Not only are my fish much happier with this filter but this picture is after 2 weeks of not cleaning or replacing any water. I went through 3 filters before finding this sponge and I wouldnt look back. I had to do some research before though. Two downsides are: the instructions are kind of sketchy because they are translated from Chinese. If you do your homework and learn about this type of filter it shouldn't be an issue. 2nd is that you have to buy a air pump and tubing separately, I wish they sold them together. Overall I am very happy with my purchase and my Betas are too.

Perfect size for my 5.5 gallon! I was afraid this filter would be too big or small for my tank, but the size couldn't be more perfect. I love the corner design so it takes up minimal space unlike a round sponge filter. This filter has a nice weight to it and sinks and stays under like it should once you squeeze the sponge and allow it to soak up water. Fast shipping too! I'm very satisfied! I would post a picture, but I do not have my tank set up yet. I have only put the filter in a bucket of water to make sure it funtioned properly

Cleaned my cloudy tank in a few hours! My tank looks good as new again. I connected it with a whisper quiet air pump with a slim design, it makes a perfect combo. The sponge took some squeezing to get it to stay under water, it also needed the weight of some of my rocks. But it works and cleans the tank. At first my beta stayed at the far side of his tank, but now he swims right up to the filter and even hangs out above it. He swims more than ever, he seems happy.