It is generally accepted that the larger the discus fish tank the easier it is to keep. The larger the body of water the more stable the water conditions become within the aquarium. Discus fish will not tolerate fluctuating water quality. Expecting them to do so invariably leads to health problems. A smaller body of water is also more susceptible to pH fluctuations within an aquarium.

Always try to purchase the largest fish tank that your budget and space will allow. The minimum aquarium size I would suggest for Discus fish is 42x15x15 inches. A fish tank of this size will require more water changes to keep water conditions stable.

Remember that the small shoal of red turquoise that you have had your eye on, could grow to seven inches, given optimum water conditions and a proper feeding regime. It's always worth paying that little extra cash for a reputable brand of fish tank. The Discus fish within may represent a considerable investment. Clear Seal fish tanks and Jewel Aquariums come highly recommended.

Always install the tank on a good solid level base. The fish tank must also be sat on a polystyrene tiles or sheet, to avoid the tank base cracking due to minor imperfections in the stand or cabinet.

A quiet area of the room away from direct sunlight will be appreciated by the tank inhabitants.

It may be possible to pick up a second-hand bargain from your local paper. However watch for deep scratches, crumbling edges and the integrity of the silicon. Always disinfect the tank before use with a salt solution or an preferably a potassium permanganate solution.