Tank Sizing and Substrates for a Discus Aquarium

If are looking to set up a Discus Aquarium this page will help you understand the fundamentals of setting up a Discus tank.

Size matters

Height of Tank

The size of your tropical fish tank plays an important role in how successful you are with keeping Discus fish. Discus fish have a rounded shape, they as tall as they are long. They will typically move vertically more than they will in a horizontal direction. For this reason it is essential that your discus aquarium is at least 18 inches high, preferable more if possible. Discus will typically favour a mid-level position in the tank, so need to give them enough room above and below to make your fish content with their environment.

Length of Tank

The Size of your Discus Aquarium is importantDiscus are a very social tropical fish, and they should always be amongst other Discus. So it is advisable that you always consider having at least 4 Discus fish so that they can form a social group. Even with only 4 Discus I would suggest having at least 3 feet of width. This will allow your discus to have room to grow and move around.

Discus Aquarium size – 3 feet wide, 18″ high (min)
 

Discus Tank substrate

Many experienced keepers prefer their Discus aquarium to have no substrate, mainly for maintenance and ease of cleaning. Your Discus fish will not mind this one bit, however there are other tropical fish that make really good neighbours for the Discus. The Corydorus fish, which stays at the bottom of the tank is a perfect example of a potential neighbour to the Discus and they certainly favour a substrate. So if you are setting up a tank with the intention of having other tropical fish such as the Corydorus or a Bristlenose Pleco to help control Algae, then definitely give some consideration to their well-being too.

My personal preference is a fine sand substrate, partly because my Corydorus love it, and I also find that I can keep it fairly clean with minimal effort. Fine sand compacts well and most of the waste settles on the top. When I do a water change I simply hover the siphon slightly above the sand and the waste will lift before the sand does.