No matter what season, species, environment, etc. First of all, we must pay attention to it.
It is an eternal truth that "water" raises fish first.
Otherwise, aquatic experts will not put water in the first place of the "eight-character refinement method".
Then there is the temperature, which must be adjusted to the most suitable temperature for the growth of this fish.
Many diseases are caused by sudden changes in temperature.
There are many diseases that can be solved by temperature (such as leukoplakia)
Finally, read more and ask more questions.
There are many experts in it to solve all kinds of problems of fish friends.
I believe it will help you, too.