Review on 🐠 Penn-Plax Filt-a-Carb Replacement Activated Carbon Cartridges (2 Pack) - Enhancing Chemical Filtration in Freshwater and Saltwater Aquariums by Paula Camacho

These Penn-Plax Filt-A-Carb are the best for my in-ground filtration system. They last a very long time. I especially like how the air bubbles move through the water surface. They had a lot of air in the water, which is very good for the fish. I think it looks better than other filters, especially in a 10 gallon tank. I would recommend these little carbon filters to anyone who has an underground filtration system or is thinking of upgrading to one.