You will need to install UV sterilisers if you have green water. You should however remember that you should not rely solely on the UV unit to get rid of algae in the water. The filter that you’ve installed should be sufficient to solve the green water problem.
UV Steriliser is recommended for Koi keeping. Not only clears green water, it also sterilizes the water itself, killing harmful Bacteria that lives in the water. UV-Sterilizers kill 99% of floating algae as well as other living organisms. The do not however harm the beneficial bacteria that grow in filters and on rocks. They kill the organisms that are floating in the pond water.
How does it work?
Chlorella vulgaris, which is a single-celled green algae, require light and nutrients to survive. This algae is a sign that your pond is generally healthy, and even provide good food additive for farm animals. However, it does impede on your viewing of your koi.
The UV disrupts the internal structure of the algae, which makes them clump together to form flocculates, which can then be trapped and broken down by the filter.
When to use a UV:
You can keep the UV unit on all year round. However if you have a small pond you may find it useful in spring. You must protect your UV unit from frost if you live in a seasonal climate, especially if you run it all year round. Replace the UV lamps annually for peak performance.
How much UV do I need for my pond?
- 8-10 watts per 1000 gallons is usually recommended for green water eradication.
- 30 watts for a reduction of bacterial levels.
Take into account factors like flow rates and stocking levels.