And, if you are just starting out raising discus fish, you will see that the price of this kind of filter is enough reason not to put one in your tank. When you are setting up your discus fish tank, it is important to remember that you have to add a water conditioner in the tap water, which you will doubtlessly use. High traffic can produce high levels of stress. The acidity and hardness of the water should also be kept at an optimum level. For discus fish, the optimum water acidity would be a pH level of 6. Remember these tips and you can be sure that you will be able to take good care of your discus fish. These tips will serve as your guide in owning or keeping discus fish in your aquarium. Water chemistry is one of the most important factors that you need to understand when you plan on raising discus fish. With proper water chemistry, you can be sure that you will be able to keep your discus fish healthy as well as happy. As a discus fish owner, you need to understand that you should test the water prior to every water change. Captive fish or store bought discus fish can survive in harder water and acidic levels that can reach 6.8. They are already used to this. But for breeding purposes, stick to the natural levels that discus fish are used to. If the temperature and the acidic level falls, there will be a good chance that your discus fish will not breed and in certain cases, they can even die. So, you will want to get a fish tank that is taller than longer. For example, you may want to get a tank that is 3 feet tall and 4 feet wide. A 35 gallon tank is a good size for Discus Fish. But, you should try getting a larger fish tank. Also, with larger tanks, maintaining water quality is a lot easier than smaller tanks. In the female discus fish, the dorsal fin will seem to be rounded, while in the male, it will look more pointed. This is not distinguishable when the discus fish are still young, you can only notice this when they are in their adult stage. During spawning, you will notice that the breeding tube of the male discus fish tends to be smaller and sharper, with the female, the breeding tube will be rounder, and broader.