The fish you buy should eat the food or at least take interest in them. If the keeper says that they just fed the fish, then you should look for another place to buy a Discus Fish. As much as possible, you should buy an adult Discus Fish. This is highly recommended for first time owners of Discus Fish as adult Discus Fish costs lesser to maintain than juvenile ones. However, before you actually consider breeding your discus fish, you need to remember that breeding them can be a challenge. When it comes to breeding discus fish, there are several things that you need to keep in mind in order for you to successfully breed discus fish in your aquarium. Also, it is very important to be familiar with the behavior of the discus fish especially when they are mating or starting to breed. They need security of a school around them and getting them in groups will help in reducing their stress levels and also help in keeping them happy. Another advantage of keeping them in groups is that you are actually increasing their chances of mating and breeding and produce more discus fish, which you can keep or even sell for profit. You also have to remember that if you want to keep your Discus Fish happy, you have to keep at least 6 Discus Fish together in the same aquarium. The size and shape of the fish tank is also important. Discus Fish prefer a tall sized tank. So, you will want to get a fish tank that is taller than longer. Tips on How to Determine the Gender of your Discus Fish Its typical for any respectable aquarium owner to breed their fishes. This not only cut down on costs of purchasing new fishes, but they also pose a good challenge in growing an aquarium. So, many breeders tend to ask how they will be able to determine the gender of their discus fish. 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.