As far as I know, there are:
1. Fish tanks should be kept away from portrait decorations, such as artistic photo frames. -Harmful to the owner's health.
2. Keep the fish tank away from doors and windows-it may cause property damage.
3. The fish tank should be far away from the positive position (generally the position where the god of wealth is placed), and it is best to put it in the auxiliary position (the corner is best).
4. The fish tank should be placed between the knee and the chest-the heart of the knee (such as the ground) may make the owner get leg disease; Above the chest (such as on a high shelf), the owner may suffer from cardiovascular and cerebrovascular diseases.
In addition, the color of fish is also very particular. Red exorcises evil spirits, and black dominates evil spirits; Yellow makes money, blue makes money; Silver wealth, light brown poverty and so on.
I believe the fish tank you put on your desk won't be too big. I suggest you keep some small and docile fish. Peace of mind and good match, will not be confused by the class struggle of fish, hehe!
As for the number of fish farming, there are different opinions! Generally speaking, lucky fish should be kept in pairs, such as colorful fairy lucky crown blood parrot, golden Mary and silver Mary; It is best to keep odd numbers of fish symbolizing the fierce battle house, such as arowana and arhat.
In fact, fish farming has just begun to be ornamental and interesting, and there is far less to say. If all the above are done, I believe no one will raise fish again!
So you'd better design it according to your own ideas. Only when you are satisfied with your talents will you be happy. Happiness is the best! My statement is for your reference only.