This is a great option for people who are just starting out keeping and breeding Discus Fish as they are less expensive. You will be able to tell that which pair is the mating pair. Discus Fish will establish territory within the aquarium and you will see them defending it against the other fish in the tank. It s not that you have to look after them all the time, but they need daily care to keep them healthy and happy, and this is not a task for those who do not simply have the time, nor patience to do so. And if you re not that experienced yet in maintaining a fish tank, keeping discus fish can be quite complicated. So, keep the PH level of the water lower than normal. You also need to make sure that the aquarium is away from doors that could open. This is to prevent your Discus Fish from getting stressed. Always keep in mind that if the Discus Fish is always subjected to high levels of stress, they are more likely to get sick and die. For a pair of discus fish, a 27 gallon tank will suffice, but if you have more pairs, then you should get a bigger one, 75 gallons will do the trick for 3 to 4 pairs of discus fish. Do give your discus fish an area in the tank for them to spawn. Discus fish lay their eggs in a flat vertical surface area at the bottom of the tank. Although this will not really affect adult discus fish, it can cause huge problems for discus fry and juvenile discus fish. You have to keep in mind that gill flukes are parasites that can destroy the gills of your discus fish. They can also cause heavy breathing and irregular swimming, which can eventually leave your discus fish totally paralyzed and sink down the bottom of the tank. And, you have to keep in mind that Discus Fish are rather sensitive when it comes to water quality. Water quality is very important if you plan on keeping a Discus Fish. Try to keep the water clean and also its chemistry stable. You have to at least change 50 percent of the water once a week and you have to make sure that the PH level is also stable.