Tools for discus aquariums

Check off the symptoms you observe (darkening, refusing food, white feces, rapid breathing) and get a list of likely causes plus steps to verify. Useful before applying any treatment — many symptoms have multiple causes.

Recommends the weekly percentage (25–50%) based on volume, population and stage (juveniles need daily changes of 30–50%, adults only 1–2 changes/week). Includes the Seachem Prime dose for dechlorination.

Calculates the gross volume from L×W×H and the real usable volume after subtracting the substrate, hardscape and water level below the rim. The usable volume is what you use for treatment dosing and water change calculations.

Estimates the daily quantity in grams and the meal frequency based on stage: fry (5–7 meals/day), juveniles (3–4 meals), adults (2 meals). Prevents overfeeding — the main cause of ammonia problems in new tanks.

A realistic budget: electricity (200–300W heater, filter, light), water for changes, food, dechlorinator and filter consumables. Useful before you start — a 300L tank can cost the equivalent of 30–50 EUR/month to maintain.

An indicative calculator for common products (eSHa HEXAMITA, eSHa Gdex, Seachem MetroPlex, praziquantel, metronidazole) based on the real volume of your tank. Note: always check the manufacturer's instructions — the calculator does not replace official guidance.

Calculates the exact proportion of reverse osmosis water and tap water to reach your target TDS: 100–200 ppm for display, 80–120 ppm for breeding, under 30 ppm for wild Heckel/Altum.

The optimal number of discus based on volume: the general rule is 40–50L/adult discus. For a harmonious group you need at least 5–6 specimens — discus are shoaling fish and get stressed alone or in pairs.

Quick conversions between common units: °C ↔ °F (temperature), TDS ppm ↔ µS/cm (conductivity), °dGH ↔ mg/L CaCO₃ (hardness). Includes the pH scale with the optimal zones marked for discus (6.0–6.8).