There certainly will be some costs, but if you do it right, you will be saving money in the long run. In starting out, you have two options. First is the certain option, which is more expensive though. All you have to do is go to a pet shop and buy a breeding pair. This can set you back about 300 dollars. So, in maintaining the water of your tank, you not only need to keep it clean, you also have to get the right pH levels and the proper temperature which will simulate the waters where the discus fish came from, which is the Amazon river. Changing the water in your tank should be done at least once or twice a week. A lot of discus fish owners today have seen the great potential in making money of their pets. First off, you have to realize that the discus fish is not just like your ordinary goldfish, they can be quite costly and selling their fry has the possibility of making them money. You too can be able to venture in this, providing you know what you are doing. Before, because of its limited supply, only a selected few would be able to get their hands on a discus fish, let alone a handful of them, luckily today, many are now able to get their hands on them, and if you re one of those lucky persons, then you should know how to provide them a good environment so that they can leave healthy and stress free. For this reason alone, you may want to get the largest and deepest aquarium that your home and budget can allow. You also have to remember that discus fish are social creatures. They live and travel in groups of at least 6. So, make sure that you have at least 6 discus fish swimming around in your aquarium in order to keep them happy and prevent them from getting lonely. The drawback is that breeding is not a hundred percent guaranteed but for most people, this method never failed. 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.