Referenzübersicht der in Aquaponik, Hydroponik und Pflanzenbiologie gebräuchlichen Messgrößen und Einheiten — mit ISO-Norm, typischen Wertebereichen, Umrechnungsfaktoren und einem direkten Härtekalkulator (Reiter „? Wasser" → Abschnitt Härtekalkulator). Reference overview of measurement quantities and units used in aquaponics, hydroponics and plant biology — with ISO standard, typical ranges, conversion factors and a direct hardness calculator (tab "? Water" → Hardness Calculator section).
| ParameterParameter | Symbol | EinheitUnit | NormStandard | Typischer BereichTypical Range | Umrechnungen / HinweiseConversions / Notes |
|---|---|---|---|---|---|
| pH-WertpH Value | pH | — dimensionslos— dimensionless | ISO 10523 | AP6.8–7.4 HP5.5–7.0 |
Logarithmisch; pH 7 = neutral 1 Einheit = 10× KonzentrationsunterschiedLogarithmic; pH 7 = neutral 1 unit = 10× concentration difference |
| Elektrische LeitfähigkeitElectrical Conductivity | EC | mS/cm | ISO 7888 | AP0.3–1.5 mS/cm HP1.2–3.5 mS/cm |
1 mS/cm = 1000 µS/cm EC ≈ TDS / 640 |
| Gesamtgelöste FeststoffeTotal Dissolved Solids | TDS | mg/L | — | AP200–800 mg/L HP600–2500 mg/L |
1 mg/L ≡ 1 ppm TDS ≈ EC × 500–700 |
| Gelöster SauerstoffDissolved Oxygen | DO | mg/L | ISO 5814 | >5 mg/L · Ideal >7>5 mg/L · Ideal >7 | 1 mg/L ≈ 0.70 mL/L (20 °C) Sättigung ~9.1 mg/L bei 20 °CSaturation ~9.1 mg/L at 20 °C |
| TemperaturTemperature | T | °C | ISO 80000‑5 | AP18–30 °C HP16–28 °C |
°C = (°F − 32) × 5⁄9 K = °C + 273.15 |
| Relative LuftfeuchtigkeitRelative Humidity | RH | % | ISO 80000‑5 | 50–80 % | RH = (p_w / p_sat) × 100 Taupunkt beachten (Botrytis!)Watch dew point (Botrytis!) |
| SättigungsdampfdruckSaturation Vapor Pressure | psat | Pa / hPa | ISO 80000-5 | 0.61–123 hPa (0–50 °C) | psat(T) = 6.1094 × exp(17.625·T / (243.04+T)) [hPa] Temperaturabhängiger Maximaldampfdruck von WasserTemperature-dependent maximum vapor pressure of water |
| TaupunkttemperaturDew Point Temperature | Td | °C | ISO 80000-5 | -45–60 °C | γ = ln(RH/100) + 17.625·T/(243.04+T) Td = 243.04·γ / (17.625−γ) Kondensationsrisiko bei Oberflächentemperatur < TdCondensation risk when surface temperature < Td |
| Ammonium / AmmoniakAmmonium / Ammonia | NH₄⁺/NH₃ | mg/L (als N)(as N) | ISO 7150‑1 | NH₄⁺ <1 mg/L NH₃ <0.1 mg/LNH₄⁺ <1 mg/L NH₃ <0.1 mg/L |
NH₄⁺(mg/L) × 0.777 = NH₄⁺-N NH₃ toxisch ab ~0.02 mg/L-NNH₃ toxic above ~0.02 mg/L-N |
| NitritNitrite | NO₂⁻ | mg/L (als N)(as N) | ISO 6777 | <0.5 mg/L | NO₂⁻(mg/L) × 0.304 = NO₂⁻-N Fischgiftig; Nitrifikation prüfenToxic to fish; check nitrification |
| NitratNitrate | NO₃⁻ | mg/L (als N)(as N) | ISO 7890‑3 | AP5–150 mg/L HP100–200 mg/L |
NO₃⁻(mg/L) × 0.226 = NO₃⁻-N 1 mmol/L = 62.0 mg/L NO₃⁻ |
| CarbonathärteCarbonate Hardness | KH | °dH | ISO 9963‑1 ① | AP3–8 °dH HP2–6 °dH |
1 °dH → HCO₃⁻ 21.8 mg/L 1 °dH → CaCO₃ 17.8 mg/L ▼ Kalkulator untenCalculator below |
| DurchflussFlow Rate | Q | L/h | ISO 80000‑4 | systemabhängigsystem-dependent | 1 m³/h = 1000 L/h 1 L/min = 60 L/h |
| RedoxpotenzialRedox Potential | Eₕ | mV | — | +200–+400 mV (aerob)+200–+400 mV (aerobic) | Bezug NHE; positiv = oxidierend <200 mV → O₂-Mangel prüfenReference NHE; positive = oxidizing <200 mV → check O₂ deficit |
Härtewert eingeben → alle gelösten Ionen sofort in mg/L, mmol/L und mEq/L. Keine Umrechnung im Kopf. Gilt für Karbonathärte (KH); permanente Härte enthält kein HCO₃⁻. Enter any hardness value → all dissolved ions instantly in mg/L, mmol/L and mEq/L. No mental conversion needed. Applies to carbonate hardness (KH); permanent hardness contains no HCO₃⁻.
⓵ Mitteleuropäisches Leitungswasser ≈ 65 % Ca, 35 % Mg. ⓶ HCO₃⁻ ist immer gleich, unabhängig vom Ca/Mg-Verhältnis (beide Ionen sind zweiwertig). ⓵ Central European tap water ≈ 65 % Ca, 35 % Mg. ⓶ HCO₃⁻ is always the same, regardless of Ca/Mg ratio (both ions are divalent).
| IonIon | mg/L | mmol/L | mEq/L |
|---|---|---|---|
| Anion — Puffer / Alkalität Anion — Buffer / Alkalinity | |||
| HCO₃⁻ HydrogenkarbonatBicarbonate |
— | — | — |
| CO₃²⁻ Karbonat (pH>8.3)Carbonate (pH>8.3) |
≈ 0 bei pH <8.3 (vernachlässigbar) ≈ 0 at pH <8.3 (negligible) | ||
| Kationen — Erdalkalimetalle Cations — Earth-alkali metals | |||
| Ca²⁺ (— %) KalziumCalcium |
— | — | — |
| Mg²⁺ (— %) MagnesiumMagnesium |
— | — | — |
| Summen / ÄquivalenteTotals / Equivalents | |||
| Erdalkali ges.Earth-alkali tot. | — | — | — |
| CaCO₃ Äquiv.equiv. | — | ReferenzsubstanzReference substance | |
| EinheitUnit | WertValue |
|---|---|
| °dH (DE) | — |
| °e / °Clark (EN) | — |
| °fH (FR) | — |
| °rH (RU) | — |
| ppm CaCO₃ (US) | — |
| mg/L CaCO₃ | — |
| mg/L CaO | — |
| mEq/L | — |
| mmol/L | — |
| 3 °dH | → 65.3 mg/L HCO₃⁻ | MinimumMinimum |
| 5 °dH | → 108.9 mg/L HCO₃⁻ | OptimalOptimal |
| 8 °dH | → 174.2 mg/L HCO₃⁻ | ObergrenzeUpper limit |
→ 10 / 56.08 = 0.1783 mmol/L Erdalkali
KH-Gleichgewicht (pH 6.5–8.3):
Ca²⁺ + 2 HCO₃⁻ ⇌ CaCO₃↓ + H₂O + CO₂↑
HCO₃⁻ = 2 × 0.1783 × 61.02 = 21.77 mg/L
Ca²⁺ = 0.1783 × 40.08 = 7.14 mg/L (100% Ca)
Mg²⁺ = 0.1783 × 24.31 = 4.33 mg/L (100% Mg)
HCO₃⁻ ist konstant — beide Ionen sind zweiwertig! 1 °dH ≡ 10 mg CaO/L (M = 56.08 g/mol)
→ 10 / 56.08 = 0.1783 mmol/L earth-alkali
KH equilibrium (pH 6.5–8.3):
Ca²⁺ + 2 HCO₃⁻ ⇌ CaCO₃↓ + H₂O + CO₂↑
HCO₃⁻ = 2 × 0.1783 × 61.02 = 21.77 mg/L
Ca²⁺ = 0.1783 × 40.08 = 7.14 mg/L (100% Ca)
Mg²⁺ = 0.1783 × 24.31 = 4.33 mg/L (100% Mg)
HCO₃⁻ is constant — both ions are divalent!
| ParameterParameter | Symbol | EinheitUnit | NormStandard | Typischer BereichTypical Range | Umrechnungen / HinweiseConversions / Notes |
|---|---|---|---|---|---|
| Photosynthetische PhotonenflussdichtePhotosynthetic Photon Flux Density | PPFD | µmol/(m²·s) | ASABE S640 ② | Blattgemüse: 100–400 Früchte: 400–800 µmol/(m²·s)Leafy veg.: 100–400 Fruiting: 400–800 µmol/(m²·s) |
1 µmol/(m²·s) ≈ 54 lx (Tageslichtdaylight) ③ ≈ 0.218 W/m² (550 nm) |
| TageslichtintegralDaily Light Integral | DLI | mol/(m²·d) | — | Salat 12–17 Tomate 20–30 mol/(m²·d)Lettuce 12–17 Tomato 20–30 mol/(m²·d) |
DLI = PPFD × 3600 × h / 10⁶ Bsp: PPFD 200, 16 h → DLI ≈ 11.5Ex: PPFD 200, 16 h → DLI ≈ 11.5 |
| BeleuchtungsstärkeIlluminance | Eᵥ | lx | ISO 80000‑7 | 10 000–50 000 lx | 1 lx = 1 lm/m² 1 lx ≈ 0.0185 µmol/(m²·s) ③ |
| BestrahlungsstärkeIrradiance | E | W/m² | ISO 9060 | — | 1 W/m² (PAR) ≈ 4.57 µmol/(m²·s) (näherungsweise bei 550 nm)(approx. at 550 nm) |
| WellenlängeWavelength | λ | nm | ISO 80000‑7 | PAR: 400–700 nm | 1 nm = 10⁻⁹ m Blau 400–500 | Rot 600–700 nmBlue 400–500 | Red 600–700 nm |
| FotoperiodePhotoperiod | — | h/d | — | 12–18 h/d | Kurztag <12 h · Langtag >14 h Neutral 12–14 hShort-day <12 h · Long-day >14 h Neutral 12–14 h |
| LichtstromLuminous Flux | Φᵥ | lm | ISO 80000‑7 | — | 1 lm = 1 cd·sr Lichtausbeute: lm/WLuminous efficacy: lm/W |
| ElementElement | Symbol | EinheitUnit | ISO | Bereich (HP)Range (HP) | Umrechnungen / HinweiseConversions / Notes |
|---|---|---|---|---|---|
| ▸ Makronährstoffe▸ Macronutrients | |||||
| StickstoffNitrogen | N | mg/L | ISO 11905‑1 | 100–250 mg/L | 1 mmol/L NO₃⁻ = 14.0 mg/L N Formen: NO₃⁻-N, NH₄⁺-NForms: NO₃⁻-N, NH₄⁺-N |
| PhosphorPhosphorus | P | mg/L | ISO 6878 | 30–60 mg/L | 1 mmol/L H₂PO₄⁻ = 31.0 mg/L P P₂O₅ × 0.436 = P |
| KaliumPotassium | K | mg/L | ISO 9964‑3 | 150–350 mg/L | 1 mmol/L K⁺ = 39.1 mg/L K K₂O × 0.830 = K |
| KalziumCalcium | Ca | mg/L | ISO 7980 | 100–200 mg/L | 1 mmol/L Ca²⁺ = 40.1 mg/L Ca CaO × 0.715 = Ca |
| MagnesiumMagnesium | Mg | mg/L | ISO 7980 | 30–60 mg/L | 1 mmol/L Mg²⁺ = 24.3 mg/L Mg MgO × 0.603 = Mg |
| SchwefelSulfur | S | mg/L | ISO 10304‑1 | 60–120 mg/L | 1 mmol/L SO₄²⁻ = 32.1 mg/L S SO₄²⁻ × 0.333 = S |
| ▸ Mikronährstoffe▸ Micronutrients | |||||
| EisenIron | Fe | mg/L | ISO 6332 | 1–5 mg/L | 1 mg/L = 17.9 µmol/L Chelat-Fe bevorzugt (EDTA/DTPA)Chelated Fe preferred (EDTA/DTPA) |
| ManganManganese | Mn | µg/L | ISO 11885 | 200–500 µg/L | 1 mg/L = 1000 µg/L Phytotoxisch ab >2 mg/LPhytotoxic above >2 mg/L |
| ZinkZinc | Zn | µg/L | ISO 11885 | 50–100 µg/L | 1 mg/L = 1000 µg/L |
| BorBoron | B | µg/L | ISO 9390 | 100–300 µg/L | B(OH)₃ × 0.175 = B 1 mg/L = 1000 µg/L |
| KupferCopper | Cu | µg/L | ISO 11885 | 10–50 µg/L | 1 mg/L = 1000 µg/L Fischgiftig ab >100 µg/LToxic to fish above >100 µg/L |
| MolybdänMolybdenum | Mo | µg/L | ISO 11885 | 10–50 µg/L | 1 mg/L = 1000 µg/L N-Assimilation (Nitratreduktase)N-assimilation (nitrate reductase) |
| ParameterParameter | Symbol | EinheitUnit | ISO | Typischer BereichTypical Range | Umrechnungen / HinweiseConversions / Notes |
|---|---|---|---|---|---|
| BesatzdichteStocking Density | ρ | kg/m³ | — | AP15–60 kg/m³ | 1 kg/m³ = 1 g/L Intensiv >40 kg/m³ (RAS)Intensive >40 kg/m³ (RAS) |
| FutterverwertungsquotientFeed Conversion Ratio | FCR | — (dimensionslos)— (dimensionless) | — | 1.0–2.0 | Futter(g)/Zuwachs(g) FCR <1.5 = gut; Ziel ~1.1Feed(g)/Gain(g) FCR <1.5 = good; target ~1.1 |
| Spez. WachstumsrateSpecific Growth Rate | SGR | %/d | — | Fische: 1–5 %/dFish: 1–5 %/d | SGR = (ln W₂ − ln W₁)/t × 100 W in g; t in Tagendays |
| PflanzenbiomassePlant Biomass | — | g/m² | — | je nach Kulturcrop-dependent | 1 kg/m² = 10 t/ha FG/TG-Verhältnis ~10–15FW/DW ratio ~10–15 |
| BlattflächenindexLeaf Area Index | LAI | m²/m² | — | 1–5 m²/m² | Blattfläche/Bodenfläche (dimensionslos) Dichte Bestände: LAI >3Leaf area/Ground area (dimensionless) Dense canopy: LAI >3 |
| CO₂-KonzentrationCO₂ Concentration | c(CO₂) | µmol/mol | ISO 80000‑9 | 400–1500 µmol/mol | 1 µmol/mol ≡ 1 ppm (Gasegases) Ambient ~420 ppm; Düngung 800–1200Ambient ~420 ppm; enrichment 800–1200 |
| TranspirationsrateTranspiration Rate | E | g/(m²·h) | — | kulturabhängigcrop-dependent | 1 L/(m²·d) = 1 mm/d Stomata-gesteuert (VPD-abhängig)Stomata-controlled (VPD-dependent) |
Alle Angaben ohne Gewähr · Wertebereiche sind Richtwerte; Optimalwerte variieren nach Systemdesign, Tierart und Kulturpflanze. ① ISO 9963-1 defines total alkalinity; KH ≈ alkalinity in carbonate-buffered systems (aquarium convention). ② ASABE S640 (2017) is not an ISO standard but the recognized technical standard for PPFD/PAR measurement in plant production. ③ Lux ↔ µmol/(m²·s): highly lamp-dependent; factor ~54 applies to daylight spectrum.
All data without guarantee · Value ranges are indicative; optimal values vary by system design, species and crop.
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