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Advantages of Green Water

Green water, sometimes called blue water, is a phenomenon in which the water turns green. This phenomenon can occur in any aquarium where ornamental fish are kept, including goldfish. In this article, we will explain the benefits of green water and how to deal with it.

What is Green Water?


Green water, sometimes called blue water, is a phenomenon in which water turns green.This phenomenon can occur in any aquarium or container where ornamental fish are kept, including goldfish.Green water is caused by the proliferation of green algae (e.g., chlorella), green beetles, and other phytoplankton.Phytoplankton is commonly found in everyday water. And Chlorella, one of the causes of green water, has been gaining attention in recent years as a health food.

Advantages of Green Water

Greenwater is a problem that will arise at some point in keeping ornamental fish. There are three main benefits of green water that can help you make the most of green water, which is generally frowned upon.

1, Operation as bait

2, Blindfold substitute

3, Measures to prevent water temperature rise

These benefits will now be explained in detail.

Details of Benefits

Operation as bait


Causes green water.Phytoplankton is very healthy because of its rich protein, mineral, and vitamin components. And these components are very necessary for the growth of the fry.Therefore, it can be used as food for fry such as goldfish and killifish. However, increasing the number of times they are fed increases the risk of disease and death due to poor water quality. Therefore, by rearing fry in green water, you can reduce the amount and frequency of feedings and avoid deterioration of water quality by creating a constant supply of food.


Some people who dislike green water say that the green color of the water makes the creatures invisible and removes the enjoyment of the water as an ornamental fish. It is true that the green color of the water makes it difficult to see the ornamental fish,Invisibility to humans means invisibility to creatures (cats, birds, etc.) that target creatures living in green water.Even if they were targeted, the odds are that they would give up because it is difficult to target them reliably. If you have a neighbor who has a critter that comes to target you or has been taken in the past, please consider trying to keep it in green water.

Measures to prevent water temperature rise

In the summer, the water temperature in some places can rise to a temperature that can kill the creatures being kept.By keeping the fish in green water, the phytoplankton absorbs sunlight, which helps control the rise in water temperature.This will reduce the burden on the creature's body. Some growers even intentionally keep their ponds in green water during the summer. However, it is important to note that the water temperature will still rise even if the rise is suppressed, so it will be even more effective if humans take measures to prevent direct sunlight exposure. If you are exposed to direct sunlight in the summer, please consider using green water.

How to deal with green water


While the above has explained the advantages of green water, the disadvantage is that the water is green, so you cannot see the creatures. The risk of not being able to see them is that you will be one step slower to notice illnesses and other problems. And if the water in places where you want creatures to be visible (such as a pond in an inn or a temple) is green, you lose the fun of "seeing" the creatures by not being able to see them. So I'll explain two ways to make it harder for water to become green water. first,Avoid direct sunlight as much as possible.Plant bacteria in the water increase rapidly through photosynthesis when exposed to sunlight. To avoid green water, keep them in a place that is not exposed to direct sunlight,Avoid places where water temperatures rise.This is connected to the first point about not exposing them to sunlight, but high water temperatures can cause the plant bacteria to become more active, which in turn can lead to green water. Therefore, if there is a place where it is difficult to get direct sunlight or high humidity, keep them there. On the contrary,If you want to generate green water, place the plant in a place with direct sunlight and high water temperature, and it will become green water in about half a day to two days.