Feng Shui is the ancient Chinese practice of achieving harmony with specific placement of certain objects in your house or office. How does this pertain to you and especially your fish tank? A person according to Feng Shui has an energy source called Qi. Qi is the person's "energy" and can be affected postively or negatively by their surroundings. Luck, health and prosperity are usually the main focus for Feng Shui.
Having a fish tank or aquarium can help increase positive Feng Shui in your life. It is said that it can help increase wealth and luck by having one in your house or office. The main belief is to have 8 goldfish (as gold symbolizes wealth/luck) and 1 black fish (to absorb any bad luck). Most common fish tanks practicing this belief uses goldfish. I have a goldfish tank in my office. Keeping a tank of 9 fishes in your office/home sounds simple but requires much more.
In order for a good flow, you need to keep your tank cleaned and to make sure your aquarium is healthy. Unclean tanks and sick fish can cause "bad chi" to emit from it and instead of giving you good chi, it'll do more harm than good. There's alot more feng shui belief about this so if you find it interesting, let me know what else you find out.
Now I know most of you don't have goldfish tank but you can take the same principles and apply it to your own fish tanks.
1. Keep your fish tank clean
To me personally, it's just more enjoyable watching a clean tank than a dirty tank. So after writing this, I will be cleaning my goldfish tank at the office today.