Keep some small koi fish, the size of the fish tank depends on the number. Generally, a fish tank with a depth of 1.2 to 1.5m can meet the needs of feeding koi fish.
The water with large water depth is equivalent to a container, and the total amount of oxygen dissolved in it is naturally large. Dissolved oxygen mainly contacts the air through the water surface, and the oxygen in the air dissolves into the water.
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Matters needing attention in raising koi fish:
1. With sufficient food, the growth rate of koi fish will be very fast, which can generally grow to more than one meter long. So if you choose a fish tank, you must have a bigger size. Generally, a fish tank of more than one meter and five meters is more suitable.
And a fish tank can't keep too many koi fish, otherwise there will be no free living environment. Although the newly bought koi fish is only a few tens of centimeters long, it will grow quickly. If there are many, it is best to put them in different fish tanks.
2. Although koi fish has low requirements for water quality, fish friends still need to change water regularly. It is necessary to install a filter to change the water in a large fish tank, so as to filter the impurities in the water while delivering oxygen. New fish friends can only change about one-third of the water at a time to keep the ecological environment in the fish tank stable.
3. koi fish is an omnivorous fish. Newcomers should never plant aquatic plants in fish tanks to avoid being eaten by koi fish. Moreover, the aquatic plants bitten by koi fish will cause water pollution and easily produce bacteria, which is unfavorable to the growth of fish.
But fish friends can put some ornaments such as stones and driftwood in the fish tank, and lay some sand stones at the bottom, which can make koi fish's life more comfortable and natural.
4. Although the fish tanks in koi fish don't need to be heated in winter, the fish can survive the winter normally, but the activity is reduced. Fish friends must dry before changing water. It's best to wait for the water temperature inside and outside to approach before changing water, otherwise changing water in winter will easily make koi fish unable to adapt.