Water Chemistry Mastery
Why discus need warmer, softer, more acidic water than most tropical fish — and how to hit and hold those numbers.
Care fundamentals are universal across discus strains — the color and pattern differences covered in the variety library don't change any of the water, feeding, or maintenance requirements below. Master these, and you're most of the way to a thriving tank.
Why discus need warmer, softer, more acidic water than most tropical fish — and how to hit and hold those numbers.
Bare-bottom vs. planted, tall tanks, driftwood, and the breeding-cone question. Build the environment discus actually need.
Discus pellets, beef heart mix, and live foods — what to feed, how often, and why variety matters for color and growth.
Why discus need groups, how hierarchy forms, and compatible tankmates that won't nip fins or steal food.
Hole-in-the-head, bloat, and stress-related color loss — spotting them early and treating the real cause.
Why discus keepers change water more often than almost any other freshwater hobbyist, and how to make it sustainable.
If you're setting up your first discus tank, read in this order:
Then, once your tank is established and fish are in, read Common Diseases and Social Dynamics so you can recognize problems before they spiral.
If you remember nothing else, remember this:
Get these five things right, and everything else becomes easier.
82–86°F (28–30°C) — well above what most tropical community fish tolerate long-term, which is the main reason discus get a species-only tank. See water chemistry for the full parameter breakdown.
Serious keepers change 25–50% of tank volume every one to two days, especially with juveniles or a breeding pair. No filter, however large, replaces this routine — details in water quality & maintenance.
A quality discus-formulated pellet as the staple, supplemented with beef heart mix, frozen bloodworms, and live foods for variety and conditioning. Full schedule in the feeding guide.
Usually a stress symptom rather than a disease — new water, an undersized group, aggressive tankmates, or a chemistry swing. Test water first; see common diseases and social dynamics for how to tell the two apart.