Whether raising fish in the study will affect Feng Shui is not a question of raising fish, but where you raise fish in the study. You can raise fish next to the door of the study, which can attract wealth.
On the use of water when raising fish
Water - water is a commonly used object in Feng Shui, because there is a saying in Feng Shui that "Mountains manage people, water manages wealth", so it is appropriate to place water in your home. The position will have the effect of attracting wealth. The simplest and quickest way is to put water next to the door, because when the door is opened, the gas emitted by the water will be brought into the house, and water is wealth, that is, the gas will be indirectly brought into the house.