Repl. foam blue wide ProfiClear M3 INT

For ProfiClear M3. The heart of a filter is its filter sponges: Blue filter sponges have coarse filtration properties, as they develop their full function at a high water flow rate. This means that larger dirt particles get caught directly in the sponge during the flow and are thus removed from the pond water. However, filter sponges not only perform the classic filtration function, but also provide plenty of living space for tiny bacteria. This small biological oasis ensures the conversion of toxins produced in the pond: toxic substances are converted into harmless but algae-stimulating substances (nitrification). Together with the red and narrow blue filter sponges, these wide blue filter sponges ensure clean filter performance.