Aquascaping & Biotope

A Rio Negro recipe: a 120×50×50 cm aquarium + 2-4 cm of fine light sand + massive driftwood (Malaysian/Mopani) + 10-15 catappa leaves + 15-20 alder cones + minimal plants (Echinodorus + Amazon frogbit) + warm 3000-5000K lighting, 6-8h/day + a filter with a diffuse output, 4-5× volume/h WITHOUT activated carbon (it absorbs the tannins). Parameters: pH 5.8-6.5, TDS 50-100 ppm, KH 0-2, 28-30°C. Budget 740-2360 RON.

Malaysian driftwood is #1 — dense, dark, it sinks in 1-3 days, releases moderate-to-heavy tannins, 80-300 RON. Alternatives: Mopani (aesthetic two-tone, floats 5-14 days), Spider wood (aesthetic branching, anchoring needed), Manzanita (light, premium 80-400 RON), Redmoor (accessible European 60-200 RON). AVOID: DIY wood from the forest, conifers (fir, pine), bamboo. Preparation: boil 30-90 min + soak 1-14 days.

IT DEPENDS on the plants. They do NOT need it: Anubias, Java Fern, Bucephalandra, floating plants — they draw from fish waste. They DO need it: Echinodorus (root tabs mandatory), Vallisneria (NPK), Cryptocoryne (potassium). The low-tech strategy: Tropica Premium (only micro Fe, no NPK) 1-2 ml/50L weekly after a water change + root tabs every 4-6 months. Start with 50% of the label dose. Budget 300-620 RON/year for 250L.

Kelvin 5500-7000K (planted) or 3000-5000K (biotope), intensity 0.3-0.5 W/L, 8 hours/day with a timer + gradual sunrise/sunset. Top RO 2026 models: Chihiros A-Series (250-450 RON), Fluval Plant 3.0 (550-1400 RON), Twinstar E-Line (450-1000 RON), Aquael Leddy Slim Plant (180-350 RON budget). Floating plants (Amazon frogbit) over 30-50% of the surface diffuse the light = more relaxed discus.

HYBRID for most (the recommendation): fine sand + Anubias/Java Fern on wood + Amazon frogbit. Aesthetics + ease (710-1360 RON, 250L). PLANTED for experienced aquascape lovers (+800-2000 RON, 30-45 min/day of maintenance). BARE-BOTTOM for professional breeders (maximum hygiene, +30-50% fry growth, instant diagnosis, minimal cost, but a clinical look). Plants do NOT replace water changes!

Compatible: Nature Aquarium (Takashi Amano, #1 recommended), Amazon Biotope (authentic Rio Negro), Jungle Style (dense low-tech plants), Iwagumi + wood (hybrid). TO AVOID: pure Iwagumi (an HC carpet needs 24°C + heavy CO2), classic Dutch (colorful Rotala/Ludwigia die at 29°C), Asian/African biotopes (incompatible temperature). Rules: 40-50% open surface, height at least 45 cm, Golden Ratio (focal point at 1/3, NOT the center), plants that tolerate 29°C.

NEVER copper-based algicides (old Sera Algovec, JBL Algol, API Algaefix) — TOXIC to discus. Safe solutions by type: brown diatoms = wait + Otocinclus; black BBA = Seachem Excel 5ml spot-applied with the filter off for 1-2 min + reduce direct flow; green hair algae = manually with a toothbrush + Amano shrimp; greenwater = a 5-9W UV sterilizer. Universal prevention: 30-50% water changes per week + lighting max 8h/day + floating plants over 30-50% of the surface.

Minimum 200L for 5–6 discus. 250–300L recommended for a healthy group with room for hierarchy. Below 150L = chronic stress, high mortality.

An external filter with a flow rate of 4–6× the volume/h. For 250L → 1000–1500 L/h. Trusted brands: Eheim Classic 600, Fluval 307, JBL CristalProfi e1502. Avoid small internal filters.

Cycling = growing the beneficial bacteria that turn toxic ammonia into nitrite, then into less dangerous nitrate. It takes 4–6 weeks. Without it, discus die within 48–72h from poisoning.

Ask for filter sponges from a breeder with a mature aquarium — a ready-made bacterial colony, cycling in 3–7 days. Or use Seachem Stability/Tetra SafeStart according to the instructions.

For beginners: bare-bottom (no substrate) is easier to clean and lets you spot health problems. Fine sand substrate (0.5–1mm, max 3cm layer) is fine for aesthetics, but needs weekly vacuuming. Avoid gravel — it traps waste.

The rule is 1W/liter (1.2W/L in winter). For 200L → 200W total, ideally 2 heaters of 100W (safety against failures). Trusted brands: Eheim Jäger, Aquael Comfort Zone, JBL ProTemp, Fluval E. Add an external Inkbird thermostat for ±0.2°C precision.

Power of 0.3–0.5 W/L for a moderately planted tank, 6500K full spectrum, 8–10 hours/day with a mandatory timer. RO 2026 models: Chihiros A2 Plus (350–550 RON), Aquael Leddy Slim Plant (250–450 RON), Twinstar S-Line premium (800–1200 RON). Discus prefer diffuse light.

Top 4 'set-and-forget' plants: Anubias (any variety, on driftwood), Microsorum pteropus (Java Fern), Cryptocoryne wendtii, Ceratophyllum demersum (floating). All tolerate 30°C, need no CO2, low light. Avoid Glossostigma, HC Cuba, Cabomba — they die above 26°C.

Below 300L → external filter (Eheim, Fluval, JBL, 300–1500 RON, plug & play). Above 400L → a sump becomes feasible (1500–5000 RON, more filter volume, hides equipment). Beginners and locations sensitive to flooding: the external filter is always the safe choice.

1 Terminalia catappa leaf per 30L of water (200L → 6–8 leaves). Add gradually, 2–3/week, to avoid a sudden pH drop. Benefits: antibacterial tannins, natural pH 6.0–6.5, reduced stress, encourages breeding. Replace every 3–4 weeks.

Temperature 29–30°C, ammonia 0 ppm, nitrite 0 ppm, nitrate below 20 ppm, pH 6.0–7.5 (stability > exact value). KH ≥2 dKH (avoid pH crash). GH 3–8 dGH.

Below 28°C the discus immune system collapses → Hexamita (internal parasites) and Ich (white spot) within 1–2 weeks. The high temperature is the definition of the species, not optional.

A liquid kit is mandatory (API Master Test Kit or JBL Test, NOT strips — ±20% error). Test ammonia + nitrite daily during cycling, then weekly. KH/GH monthly.

Yes in about 80% of cases, but always test your own supply first — tap water varies enormously by region. A dechlorinator is mandatory (chloramine does NOT evaporate). Hard tap water (TDS 400+) → a 40-50% RO mix is recommended; soft tap water (TDS under 250) is often fine directly. Always dechlorinate (Seachem Prime).

It depends on your tap water. Very hard supply (TDS 400+) → YES, a home RO unit usually pays for itself within 3-6 months. Moderately soft supply → buying RO water by the bottle is often cheaper. For breeding → effectively MANDATORY. A small hobbyist with one tank → buy RO water rather than installing a unit.

NO! Pure RO water (TDS 0, KH 0) = guaranteed pH crash. Mandatory: mix it with tap water (50/50 Bucharest) OR remineralize with Seachem Equilibrium + baking soda. RO water with no minerals = death within 24h.

A sudden drop >1.0 pH within a few hours, fatal in 24–48h. It happens when KH is below 1 dKH — the water no longer buffers the acids from respiration. Prevention: KH minimum 2 dKH AT ALL TIMES, monthly testing, baking soda on hand (0.5g/10L = +1 dKH). 100% unmineralized RO water = the #1 cause.

3 safe methods: 1) RO water mixed 50/50 with tap (Bucharest) — the most stable. 2) Aquarium peat in the filter (JBL Tormec ~50g/100L) — lowers it gradually 0.3–0.8. 3) Catappa leaves + mopani wood — a 0.2–0.5 drop. Do NOT use chemical 'pH down' — it causes shocks and a pH crash when you stop.

EMERGENCY: 1) 50% water change immediately with dechlorinated water at 29°C. 2) Seachem Prime double dose (5ml/100L) — neutralizes NH₃+NO₂ for 24-48h. 3) Turn on extra aeration. 4) Stop feeding for 48h. 5) Test again in 2 hours. Causes: filter cleaned in tap water, overpopulation, incomplete cycling.

Keeping Stendker/locals: 100–200 ppm. Breeding: 50–100 ppm. Wild (Heckel, Altum): below 50 ppm. Measure with a digital TDS meter (HM Digital TDS-3 ~60 RON, reliable for 3-5 years). Calibrate 1×/year with 342 ppm solution. Strips do NOT measure TDS correctly.

Yes, but only for advanced keepers (NOT beginners). Strict rules: KH minimum 3–4 dKH, a solenoid on a timer (off at night), extra aeration at night, weekly pH monitoring. A complete JBL/Aquario system 300-500 €. For 90% of keepers: low-tech without CO2 is the correct choice with Anubias/Java Fern/Echinodorus plants.