Exo Terra Fine Foam (FX-200 Filter) – A fine-pore filter foam insert for the Exo Terra FX-200 Turtle Filter. It is custom-shaped to fit the filter, ensuring no water bypasses around it. The fine foam pad catches small particles and debris, polishing the water for exceptional clarity. It also provides a large surface area for beneficial bacteria colonization, contributing to biological filtration. By removing fine waste and supporting the nitrogen cycle, this fine foam helps maintain healthy, odor-free water for aquatic turtles and other tank inhabitants. Replace as needed to keep filtration effective and water quality high.