*Product May Be Subject To Extended Lead Times. The UltraZap 5L Bio Ball Filter and 8W UV Steriliser Combo offers an all-in-one water filtration solution for small to medium-sized ponds, combining mechanical, biological, and UV filtration for superior water clarity and quality. Water first passes through the 8W UV steriliser, which effectively eliminates algae, harmful bacteria, and pathogens—helping to prevent green water and maintain a healthy aquatic environment. Following UV treatment, the water flows into a compact 5-litre bio filter filled with specially-designed bio balls. These provide a large surface area for beneficial bacteria to colonize, which naturally break down toxic ammonia and nitrites into safer nitrates through biological filtration. Easy to set up and maintain, this combo system ensures clear, clean, and healthy water for fish, plants, and other aquatic life—ideal for ornamental ponds, water features, and hobbyist setups. Pond cap 2500L. Includes Bio Balls