This sponge filter works great in my 20 gallon long tank. This is my first tank. As I expand to a larger tank, I will purchase more.

Best shipping experience I’ve had. Got it in my 36 gallons tank and it’s doing beautifully. THANK YOU AQUARIUM CO—OP.

Love these filters I would give it a 5 star but the easy flow collar needs to be maintain often because the flow will slow down dramatically

Love the flow and maybe I’m weird but I actually like the look. Perfect flow for my 75g.

Awesome 👍

Awesome 👍

Since 2021 if I’m setting up a tank no matter if I’m using a fluval canister or a HOB I’ll always have a sponge from this company in my tank!

The Green Easy Flow Sponge Filter (coarse) has been an outstanding addition to my aquarium setup. The build quality is excellent, and the coarse sponge strikes the perfect balance between strong filtration and easy maintenance. Water clarity improved noticeably within a short time, and the fish seem to appreciate the gentle, consistent flow.

What I love most is how quiet and efficient it is. It just works, day in and day out, without any fuss. Cleaning is quick, the materials feel durable, and it’s clear this was designed by people who genuinely understand the needs of hobbyists.

If you're looking for a dependable, low-maintenance filter that delivers great results, this one is an easy recommendation. Aquarium Co‑Op continues to impress with thoughtful, high‑quality products.

Works and pleased. Just wish the top tub was more of a 90 angle then what given. Maybe the company can have that as an add on in the future.

The dark color disappears into the tank, and otherwise it is the same ACO sponge filter, which is a little workhorse. And the fish love it!

The AC fine sponge filter is the only sponge filter I will buy. I love how well it filters. It’s like a second home for my neocaradina shrimp and is my biofilm generator. I love how the fine sponge filters extremely well. It’s perfectly gentle for shrimp and Betta fish. It is able to output water very well. I have one warning, to successfully drive this filter to its easy flow potential, you need at least a 3W air pump. I was trying to drive it with a 2W USB pump, I would get small surges and not a consistent stream of water from the top. Mine is a special case because I like the top of the spout to be above the water level. Now, if you keep the spout below the water level, you won’t run to this issue. Exceptional quality and heavy duty, none my aquariums will be left without one.

The course open texture allows for more effective cleaning of the debris out of the sponge. ones that are more dense are hard to get them clean or at least get them to look clean. I double stacked that way you can put two of them together in one corner of the tank and hide them with tall plants. great product!

I’ve owned 2 aquarium co-op sponge filters for 2 years and there are goods and bads.
First the bad:
-The “air collar” holes get clogged and is IMPOSSIBLE to clean. I have used needles, soaks, and brushes. It will not blow bubbles like it used to, basically making it useless. Even on the highest setting of the “Aquarium Co-Op Air Pump” it won’t blow more than a measly stream, making this filter trash after 2 years, here I am hunting for another small and silent filter questioning my aquarium hobby interests because i’m tired of the money sinkhole of throwing away items that should last longer.
-This FILTER AND AIR PUMP ARE NOT THAT QUIET. I turn it off EVERY night because it’s too loud in my room to sleep. And then sometimes it won’t stay off because of the battery backup setting in case of power outages. I’ll turn it off sometimes 4 times a night, because it keeps turning back on. Of course everyone has their own opinions of loud, and i’ve used other sponge filters and air pumps to compare to aquarium co-op. So far co-op is less noisy than the popular brands, but still not good enough ESPECIALLY since it doesn’t EVEN WORK ANYMORE!!

Now the good-
I like the course sponge. It is easy to clean and use and transfer. That’s pretty much it.

Seriously i’m sick of buying filters that break. One star because of that.

My only issue with this product is that the plastic pieces won’t work with every tank. For example, I have a 60 gallon with goldfish in it. I chose the large sponges for obvious reasons, but since 60 gallons aquariums aren’t that tall, no combination of parts allowed me to include the top curvy tube for added flow at the top. I’m not sure how important this is, but it’s something that I would’ve appreciated. Besides that, aquarium coop is great and this is a great sponge filter. The only one I ever consider using.

Loving the newer style sponge filters. I have 2 in my new 16 gal bookshelf. I didn't want to cut the tubes, so I just removed the bottom half of plastic, cut the sponge from the 2 existing ones I already had and then put it all back together. Fits great and the tank is only 11 inches tall.

My wife and I just got our first fish and set him up in a 5.5-gallon aquarium. So far we’re loving this filter!

It has an easy flow that provides for enough surface agitation without too strong of a current. The surface bubbles pop and get water on the plant lighting, so we’re just going to get a cover.

A potential improvement would be to have a “very short” calibration for 5.5-gallon aquariums. To get this to the right water level, I had to cut the tubes with a mini hacksaw and then use teflon tape to seal a leak that occurred from needing to insert the bent tube beyond what’s recommended. It all worked out in the end, but would it would have been nice to bypass any DIY.

Regardless, would highly recommend this filter and will be shopping with Aquarium Coop again!

I've been extremely satisfied with the durable and trustworthy quality of Aquarium Co-Op's product over the years, and this is no exception. Having not ordered a sponge filter from them in a couple years, I'm pleased with the increased flow rate thanks to the Easy Flow system. The exterior airline attachment is a major upgrade, no more anguish trying to cut airline tubing to fit inside. Shoutout to Cory and his team for developing solutions to long-standing issues in the hobby, mainly filter intakes! All around I'm impressed once again by outstanding quality from actual aquarists.

I have been using a sponge filter for many years in both a 75 gallon and a 10 gallon tank. Recently I decided a fresh filter was needed for the 10 gallon.
When I received the package (always packed with care) I opened the box and easy assembly and submerged in the tank. Next morning the water was crystal clear!
Thanks Aquarium Co-op for another great product! Love no air stone in this one!

Never have I found amore easily assembled filter. It literally hides behind my plants and adds the flow rate that I needed. I am so happy with everything I’ve purchased but the best part is their customer service. When I have ANY questions they immediately respond with a response that is understood! Thank you so much for your extreme professionalism.

Fast delivery l,easy set up ,great packaging does and works exactly as advertised

I loved these at first! In fact, I invested a great deal of money replacing the sponge filters in my tanks with these. They clog up pretty regularly. Not the sponge part. The actual lift part. The air collar clogs. It requires removing the entire top of the filter. Everything above the sponge has to be detached to clean the air collar. The bubbles get less and less, and I have to take the lift part off of the sponge and force hot water through the tiny holes in the air collar. I never have had an airstone clog up! Sadly I feel as if purchasing these was a complete waste of (a lot of) money.

I was very excited to try out this new fine pore sponge filter attached to a powerhead to see if I could scrub the water in my 65 gallon tank and make it extra crystal clear. GREAT SUCCESS!! Absolutely would recommend this sponge filter for that purpose!