Review on 🐠 Premium ALEGI 4pcs Small Aquarium Bio Sponge Filter: Ideal for 5 Gal, 10 Gal, 20 Gal Breeding Fry Betta Shrimp Fish Tank! Includes Suction Cups and Check Valves. by Missy Carter

I am very pleased with the performance of these filters. In the picture I took he is sitting in a very shallow indoor tadpole pond. Below I found stones. The portion is a bit strange as long as it floats behoto. I'll admit it was a bit annoying finally getting the thing to sink. I also feel like he could have used a little more sponge, but that's just sophistry. I think for such a tiny body of water it does a decent job and I would recommend it to people who need very gentle filtration.