For Discus fish, there are 2 consideration in tanks - tank depth and volume. Because of their size and swimming habits, a minimum of 18" is needed for tank depth, the deeper the better. Regarding volume, a good rule of thumb is that each adult discus will need 10 gallons of water. Larger tanks will also give more stable water conditions, and taking into account other considerations the minimum size for a discus show tank should be no less than 55 gallons. It is also advisable to use a rectangular tank. Not only are they cheaper, but are more efficient, because they maximize surface area. Surface area is the most important factor in buying a tank. Why? Because it is only at the surface of the tank that gas exchange occurs. (Oxygen in, Carbon dioxide out.) Assuming you have a seventy five gallon show tank, and it's biological filter is working as required, up to twenty young fish 3 inches in size, or 6 or 8 fully adult discus can comfortably inhabit the tank. An outside filter may be added to large tanks to increase basic aeration and biological filtration needs.

Keep in mind that when young discus fish are small,they grow fast and become quite large in a short period of time if fed well and water quality is maintained. If your tank is too small they will not be happy and it will quickly stunt their growth. Juvenile discus should not be kept in overly large tanks. Being a social fish, Discus tend to become very skittish in large tanks. In our hatchery, we place 6 Discus up to 1.5" in a 29-gallon tank. They will be moved tp larger tanks when they get to 2.5", and show possible signs of "pairing off". Always try to buy the largest tank you can afford for discus fish.

If breeding Discus is a consideration later on, tanks can be down sized to twenty gallons per pair. At our hatchery, 29 gallon rectangular glass tanks are utilized for every breeding pair. A bare bottomed tank with at 2