water-chemistry

name	water-chemistry
description	Style-family water targets (Ca/SO4/Cl ppm), salt addition guide, mash pH targets, SO4:Cl ratio, and carbonation reference

Water Chemistry Reference

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Style-Family Water Targets (ppm)

Style family	Ca	SO₄	Cl	Mg	Character	Notable profile
British Bitter / ESB	100–150	200–300	100–150	10–15	Sulfate-forward, dry bitter finish	Burton-on-Trent
English Porter / Stout (London)	80–100	50–100	100–150	10	Chloride-forward, round malty	London
Irish Dry Stout	100	50–100	100–150	10	Chloride-forward, enhances dry roast	Dublin
West Coast IPA / APA	100–150	150–300	50–100	10	High SO₄:Cl (2:1–4:1), dry, accentuates bitterness	Modified Burton
NEIPA / Hazy IPA	100–150	50–75	150–200	10	Inverted SO₄:Cl (1:2–1:3), soft, juicy, round	Soft/chloride
German Pilsner / Helles	50–75	20–60	20–60	5	Very soft, balanced 1:1, clean malt	Soft German
Czech Pilsner (Bohemian)	30–50	10–30	10–30	5	Extremely soft water, minimal minerals	Pilsen
Märzen / Oktoberfest	75–100	50–80	50–80	10	Balanced, slightly chloride-forward	Munich
Hefeweizen / Dunkelweizen	30–60	30–60	50–100	5–10	Soft, slightly chloride-forward	Soft German
Witbier	50–75	30–60	60–100	10	Soft, balanced, slightly chloride	Soft/neutral
Belgian Tripel / Golden Strong	50–80	20–70	20–70	10	Balanced 1:1	Brussels neutral
Belgian Dubbel / Quad	50–80	20–60	30–80	10	Slightly chloride for malt support	Brussels neutral
Saison	50–100	50–100	50–100	10	Balanced; slightly sulfate for dry finish	Neutral
American Amber / Brown	75–100	75–125	75–125	10	Balanced	Neutral
Kölsch / Alt	50–75	30–60	30–60	5	Soft and balanced	Cologne/Düsseldorf soft

Key: Ca = calcium, SO₄ = sulfate, Cl = chloride, Mg = magnesium (all in mg/L = ppm). Target ≥50 ppm Ca in most styles for yeast health and enzyme activity. Exception: Bohemian Pilsner is traditionally brewed with near-RO soft water (Ca 10–30 ppm) — authentic to the style; compensate with a healthy starter or rehydrated dry yeast.

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SO₄:Cl Ratio Guide

The sulfate-to-chloride ratio is the single most influential factor in perceived bitterness and body:

Ratio (SO₄:Cl)	Character	Best for
4:1 or higher	Very dry, crisp, accentuated bitterness	Burton Bitter, dry-hopped West Coast IPA
2:1–3:1	Dry, hop-forward, clean finish	West Coast IPA, APA
1:1	Balanced — neither malty nor bitter dominant	Most ales, lagers, neutral styles
1:2–1:3	Soft, round, full-bodied, malt-forward	NEIPA, English Mild, ESB, Stout
1:4 or higher	Very malty, full, sweet perception	Imperial Stout, Barleywine (rarely used)

Rule of thumb: If a beer tastes too harsh/astringent despite correct IBU — reduce SO₄ or raise Cl. If it tastes flabby/sweet despite correct FG — raise SO₄ or reduce Cl.

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Key Salt Additions (per 20 L batch)

Salt	Main effect	Typical use
Gypsum (CaSO₄·2H₂O)	+Ca, +SO₄ → drier, hop-forward	IPAs, bitters, hop-forward lagers
Calcium Chloride (CaCl₂)	+Ca, +Cl → rounder, malty, fuller	NEIPA, stouts, malt-forward styles
Magnesium Sulfate (MgSO₄, Epsom salt)	+Mg, +SO₄ → slight tartness	Use sparingly (<10 ppm Mg total)
Baking Soda (NaHCO₃)	+Na, raises alkalinity, raises mash pH	Dark beers only; never for pale styles
Chalk (CaCO₃)	+Ca, raises alkalinity	Dissolve in acid first; dark beers only
Lactic acid (88%)	Lowers mash pH	Universal pH adjustment
Phosphoric acid (10%)	Lowers mash pH, neutral flavor	Preferred for pale lagers (no flavor impact)

Approximate mineral additions per 20 L to hit common targets

Gypsum (CaSO₄·2H₂O):

• 1 g → +Ca ~12 ppm, +SO₄ ~28 ppm (per 20 L)
• To add +100 ppm SO₄: add ~3.6 g gypsum (also adds +43 ppm Ca)

Calcium Chloride (CaCl₂, anhydrous):

• 1 g → +Ca ~18 ppm, +Cl ~32 ppm (per 20 L)
• To add +100 ppm Cl: add ~3.1 g CaCl₂ (also adds ~56 ppm Ca)

Lactic acid (88%):

• ~0.8–1 mL per 20 L lowers mash pH by ~0.1 unit
• Adjust in small increments; measure after each addition

Worked example: West Coast IPA (20 L, starting from RO water)

Target: Ca 120, SO₄ 200, Cl 80

1. Add 7.1 g gypsum → Ca +85, SO₄ +199
2. Add 2.5 g CaCl₂ → Ca +45, Cl +80
3. Result: Ca ~130, SO₄ ~199, Cl ~80 — Ca slightly above target but acceptable; reduce gypsum to 6.5 g to bring Ca to ~120

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Mash pH Targets

Beer colour / style	Mash pH target
Pale ales, lagers, wheat beers	5.2–5.4
Amber, red, Irish ales	5.3–5.5
Brown ales, English porters	5.4–5.6
Stout, porter, dark beers	5.4–5.6

Effects of pH:

• Low pH (5.1–5.2): More fermentable, crisper, drier finish; enhances enzyme activity
• Optimal (5.2–5.4): Best enzyme efficiency, round flavor
• High pH (>5.6): Harshness, astringency, reduced enzyme efficiency, potential tannin extraction

How to measure: Always measure with a calibrated pH meter in the mash at mash temperature, or use room-temperature adjusted strips.

How to lower pH:

• Lactic acid (88%): ~1 mL per 5 L lowers pH by ~0.1 unit (neutral flavor)
• Phosphoric acid (10%): similar effect, no flavor impact (preferred for lagers)
• Acid malt (Sauermalz): 1–3% of grist lowers pH by ~0.1–0.3 unit

How to raise pH:

• Baking soda (NaHCO₃): small additions raise pH; use only for dark beers
• Chalk (CaCO₃): must dissolve in acid first; adds Ca and raises alkalinity

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Carbonation Reference (vols CO₂)

Style family	Vols CO₂	PSI at 4°C
British cask ales	1.5–1.8	5–7 psi
British bottled ales	2.0–2.4	9–12 psi
American ales (APA, IPA, Amber)	2.2–2.6	10–14 psi
German Helles / Märzen	2.4–2.6	12–14 psi
German Pilsner / Czech Pils	2.6–3.0	14–17 psi
Belgian Saison	3.0–3.5	17–21 psi
Belgian Tripel / Dubbel	2.5–3.0	13–17 psi
Hefeweizen	3.6–4.5	22–29 psi
Witbier	3.0–3.5	17–21 psi
Stout / Porter (American)	2.0–2.5	9–13 psi
Irish Dry Stout (nitro/cask)	1.0–1.5 + N₂	—

Priming sugar calculation (20 L batch): sugar_g = (target_vols − residual_CO₂) × batch_L × 4.0 for table sugar Residual CO₂ at 20°C = ~0.86 vols; at 10°C = ~1.2 vols

Example: NEIPA, 2.4 vols target, conditioned at 20°C: → (2.4 − 0.86) × 20 × 4.0 = 123 g table sugar

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Serving Temperatures

Style family	°C	°F
British ales (cask/real ale)	10–13	50–55
American ales / IPAs	7–10	45–50
German lagers (Pils, Helles)	4–7	39–45
Hefeweizen / Witbier	7–10	44–50
Belgian ales (Tripel, Saison)	7–13	45–55
Stout / Porter (draught)	10–14	50–57
Barleywine / Imperial Stout	12–16	54–61

Note: Serving too cold mutes aroma and suppresses head retention; serving too warm amplifies fusel alcohols and reduces CO₂ perception.