Review on 🐠 AQUANEAT 6.42" Long Aquarium Bio Filter Media Set - Ideal for Sump Canister Filters, Refugiums, Koi Ponds, Bakki Showers, Trickle Filters, and Aquaculture by Aliana Brown

For my freshwater swamp I took several of these and a rectangular competitor, each with their own strengths. Both are basically the same material and length, but the shape is important. They tend to roll more when placed horizontally and are slightly wider at the thick end. They stack/layer well as they are round, fit into formations, square ones don't fit perfectly and I feel that when layered gaps provide channels for water to flow better around the block/cylinder, so less likely to dead center due to having to use both which means I really like them and have ordered more since I traded in for plastic bio balloons. 2 boxes (one small, one large), none broken. another box is coming soon