- Stef wrote:
- Last spring I had numerous problems with green water. What can I do to avoid it this year.
Green water
Green water is not bad for Koi, as a matter of fact, it is very good for them and breeders often prefer to keep their water green. However, we want to see our fish. Isn’t that what Koi keeping is all about??
Very often, the quality of green water is much better than crystal clear water.
The reason why the water turns green is because of the accumulation of nutrients in the water, especially those gathered during winter. The algae blossom on these nutrients, and one must get rid of the nutrients and the algae being the cause and the result.
The other reason for green water (which is linked to the above) is because of the absence of enough bacteria, especially directly after winter, because the bacteria takes a while to grow after the winter months, as it requires enough heat to grow.
There are various options to solve the problem which can and should be used in conjunction with each other, depending on the severity of the problem.
Mechanical way
An affective UV light will clear most of the floating algae which makes your water green. However, it is not affective against blanket weed, the hardy type of algae , but these does not affect the colour of the water and can be removed manually. One have to remember that the tube is only really effective for a period of one year. So, if you have green water despite the presence of a UV light, a replacement of the tube or an additional light might be an option. It takes a few days to clear the water.
Chemical way
There are various chemicals available on the market, the most common one is "Pond Clear" which is available at most Koi outlets. It is fairly inexpensive at approximately R 75 a jar, which is good for a few treatments on an average pond. This will however cure the situation only temporarily, and it is extremely important to use the right dosages.
Plants
Another option is to introduce water plants or more plants that will use all the nutrients and compete with the algae, and the algae will gradually die off.
Bacteria
Most types of bacteria breaks down the nutrients. Introducing a bigger bio filter will cure the pond of algae, but it will take a few months. An option to get the water greener much faster, is to introduce a bale of straw into the water which will generate the right type of bacteria to limit the nutrients in the water. This is why a mature pond normally have crystal clear water, and it is difficult to maintain clear water in a newly build pond younger than 12 months.
Shade
To introduce more shade on the pond, will also help to clear the green water and to prevent it from happening again to some extent.
Salt
The increase of salt is also an option as it limits the growth of algae. However, it also limits the growth of bacteria and pond plants if the quantity is to much.
Replacement of water
Most people think that the quickest option is to do more water changes, thinking that the crystal clear water added will solve the problem. The opposite happens. New water is rich in nutrients and the algae thrive again