Review on 🐠 hygger Aquarium Double Sponge Filter with 2 Spare Sponges & Bio Ceramic Media Balls - Quiet Submersible Foam Filter for Fresh Water and Salt-Water Fish Tank by Rebecca Torres

got this for my 20g long tank. everything is as shown HOWEVER you will get BETTER results with high quality bio balls OR activated carbon filter floss in canisters. In my endless ignorance I got the middle double (up to 55g) thinking I could use an air pump rated for a tank up to 40g at 3 watts. [that's the key] The small one needs a 2.5w air pump and the medium one needs a 4w air pump. Anything else won't ensure enough water in the tank and you'll end up with dead spots without running water. This is a fantastic product if you ignore what the air pump is rated for and go by the performance specs!