Water Chemistry Mastery
Why discus need warmer, softer, more acidic water than most tropical fish — and how to hit and hold those numbers.
Discus Care Fundamentals
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.
The Core Guides
Tank Setup & Hardscape
Bare-bottom vs. planted, tall tanks, driftwood, and the breeding-cone question. Build the environment discus actually need.
Cycling a Tank for Discus
The nitrogen cycle, fishless cycling step by step, and why discus tolerate none of the shortcuts hardier fish survive.
Feeding & Nutrition
Discus pellets, beef heart mix, and live foods — what to feed, how often, and why variety matters for color and growth.
Social Dynamics & Shoaling
Why discus need groups, how hierarchy forms, and compatible tankmates that won't nip fins or steal food.
Common Diseases & Treatment
Hole-in-the-head, bloat, and stress-related color loss — spotting them early and treating the real cause.
Water Quality Monitoring
Why discus keepers change water more often than almost any other freshwater hobbyist, and how to make it sustainable.
Discus in a Planted Tank
Safe CO2 ranges, plants that tolerate 82–86°F, and how to keep chemistry stable for discus and plants at once.
Discus Lifespan
How long discus actually live, why the range is so wide, and what really shortens a discus's life — water quality, not genetics.
Where to Start
If you're setting up your first discus tank, read in this order:
- Tank Setup — physical foundation, tall tank, substrate decision
- Cycling — grow the bacteria colony before any fish goes in
- Water Parameters — temperature, pH, hardness targets
- Water Quality Monitoring — the maintenance routine that actually matters most
- Feeding — nutrition and growth
Then, once your tank is established and fish are in, read Common Diseases and Social Dynamics so you can recognize problems before they spiral.
The Non-Negotiables
If you remember nothing else, remember this:
- Discus need warm water — 82–86°F — held steady, not most tropical community temperatures.
- Water changes are the real filter. Serious keepers change 25–50% every one to two days, especially with juveniles.
- Discus are shoaling fish. Keep six or more, never a single fish or an unbuffered pair outside breeding.
- Tall tanks matter as much as gallons — discus are deep-bodied and need vertical room.
- Ammonia and nitrite must read zero, always. Discus show the effects of lapses here faster than most fish.
Get these five things right, and everything else becomes easier.
Discus Care FAQ
What temperature do discus need?
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.
How often should I change the water?
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.
What do discus eat?
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.
Why are my discus turning dark?
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.
About Pet Zone SD Team
These guides are maintained by the team at Pet Zone Tropical Fish, a San Diego freshwater specialty retailer founded in 2007 with over a decade of direct import/export experience keeping and troubleshooting discus for customers day to day.