Speaking of the tank, because the discus fish is quite large as compared to others, you should have a large enough tank to hold them. A 20 to 27 gallon aquarium would do fine. This way, you can have enough space to hold your discus fish and your aquarium ornaments and if your breeding them, future space for their spawn. This though should not be done often. As for their food, you should ask the store clerk what food they have been accustomed to. Discus fish can be picky so you need to ensure that you can, maintain the food that they usually eat. Make sure though to never overfeed your fish. The extra food will just become dirt inside the tank. You may add some ornaments in your tank. Although they can survive without them, ornaments wont only make your aquarium look good, but they can also provide shelter for them for their protection and for their spawning. Also, some plants can help clean the tank. Secondly, and to some most importantly, your aquarium water should be strictly kept at a certain level, both in temperature and in pH level. Although Angelfish can look great with the discus fish, it is not recommended for smaller discus fish tanks. This is because Angelfish can grow very large and can bully the discus fish. They may even outcompete the discus fish for food and they may also carry diseases that the discus fish are prone to catch. 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. They have vibrant color that can really please anyone who sees it swimming inside an aquarium. However, before you start to attempt raising discus fish, it is important to know that discus fish can be quite hard to keep especially for people who are just starting out in this kind of hobby. You need to remember that discus fish are temperamental creatures that need special care.