*Product May Be Subject To Extended Lead Times. The UltraZap Bio Filter 25 Litre Including Bio Balls is a premium biological filtration system engineered for large ponds, koi ponds, and aquaculture environments requiring high-performance water treatment. This advanced filter features a spacious 25-litre chamber filled with high-quality bio balls, which provide a massive surface area for beneficial bacteria to colonize. These bacteria are essential in the nitrogen cycle, breaking down toxic ammonia and nitrites into less harmful nitrates to ensure a safe, balanced aquatic environment. The included bio balls significantly boost the filter’s biological capacity, making it ideal for systems with high fish loads or organic waste. Durable, efficient, and easy to maintain, the UltraZap Bio Filter 25 Litre with Bio Balls offers long-term water clarity and supports the health of fish and plant life in even the most demanding setups. Pond cap is 12000L. Includes 350 Bio Balls