Discus have a reputation for being difficult. They are not difficult so much as unforgiving — they need warmth, cleanliness and company, and they decline visibly and quickly when any of the three slips. Give them those and they are one of the most rewarding fish in freshwater.
Keep them in groups
Discus are social and they establish a pecking order. In a group of two or three, the dominant fish has one target and bullies it relentlessly; the bottom fish stops eating and fades. Six is the practical minimum, and more is better — the aggression spreads out and stops landing on any one animal. A group of six adults wants a tall tank of 55 gallons or more.
Warmer than the rest of your fish
Discus want 82 to 86°F, several degrees above what most community fish are comfortable in. This is the single reason most discus-in-a-community-tank attempts disappoint: at discus temperature, many tank mates are stressed, and at community temperature the discus slowly stop thriving. Pick the tank around the discus, not the other way round.
Clean water, and a lot of it
Discus are more sensitive to accumulated nitrate and organics than almost anything else we sell, and growing juveniles especially so. Large, frequent water changes are the whole game — breeders raising young fish often do them daily. In a mature display tank you can ease off, but if a discus looks dark, clamped and withdrawn, water quality is the first thing to check and usually the answer.
Buying them
Look for a fish that is round rather than thin-edged, with clear eyes proportionate to the body — oversized eyes on a narrow body means a stunted fish that was underfed as a juvenile, and it will never fill out. It should be alert and interested in you, not hanging dark in a corner. Ask what it is eating.
Discus are held at our Mid-City store. Come talk through a setup before you buy — this is a fish worth planning for.
