If your pond water is still green despite the UV bulb being operational, several factors might be contributing to this issue.
Understanding the Role of UV Sterilisers
UV sterilisers are designed to maintain water clarity by targeting free floating algae. However, they are not a standalone solution for transforming poor water quality. Additional treatments or significant water changes may be necessary to address existing issues.
Factors Contributing to Green Water
- Nutrient Levels: High concentrations of phosphates and nitrates, often resulting from fish waste or overfeeding, can promote algae growth.
- Sunlight Exposure: Increased sunlight during summer months can exacerbate green water problems.
- Water Flow Rate: If the water flows through the UV steriliser too quickly, it may not effectively eliminate algae.
- UV Bulb Age: UV bulbs lose their effectiveness over time. Even if the light is on, it may not be emitting sufficient UV radiation to combat algae. It's recommended to replace the bulb annually.
Recommended Actions
- Water Testing: Conduct tests to assess phosphate and nitrate levels.
- Adjust Feeding Practices: Reduce fish feeding to lower nutrient input.
- Provide Shade: Introduce aquatic plants or other shading methods to limit sunlight exposure.
- Check Equipment: Ensure the UV steriliser is appropriate for your pond size and that the flow rate is within recommended parameters.
Additional Considerations
- Bulb Replacement: If you need to replace your UV bulb, verify the correct size for your unit. A range of replacement bulbs is available from various suppliers.
- Algae vs. Blanket Weed: It's important to distinguish between green water caused by free floating algae and issues caused by blanket weed. Each requires different treatment approaches.