Pool chemicals, explained

Ten chemicals cover nearly all residential pool care. Each page has a dosing chart by pool size, side effects to watch, and the handling rules that keep it safe.

Sanitizers (raise Free Chlorine)

🧴 Liquid Chlorine (12.5%)10.7 fl oz / 10k gal → raise Free Chlorine 1 ppm

The workhorse of pool sanitizing: fast-acting, adds no stabilizer and no calcium. Ideal for regular chlorination and shocking pools that already have enough CYA.

🧨 Cal-Hypo Shock (65–73%)2 oz / 10k gal → raise Free Chlorine 1 ppm

The standard granular shock. Strong, unstabilized chlorine — great for weekly shocking and algae kills where CYA is already sufficient.

🧂 Dichlor Granules (56%)2.4 oz / 10k gal → raise Free Chlorine 1 ppm

Stabilized granular chlorine — pH-neutral and gentle on surfaces, but every dose also raises your stabilizer. Best for new fills and spas.

⚪ Trichlor Tablets (90%)1.5 oz / 10k gal → raise Free Chlorine 1 ppm

The slow-release tablet in your floater. Convenient steady chlorination, but it acidifies the water and stacks CYA over a season — plan around both.

Balance (pH & Alkalinity)

🥄 Baking Soda22.4 oz / 10k gal → raise Total Alkalinity 10 ppm

The alkalinity raiser. 1.4 lb per 10,000 gallons lifts TA by 10 ppm. Low TA makes pH bounce around — fix TA first, then chase pH.

📈 Soda Ash6 oz / 10k gal → raise pH by ~0.2 (at TA ≈ 100 ppm)

The pH raiser. pH chemistry is non-linear, so treat doses as starting points: ~6 oz per 10,000 gallons raises pH about 0.2 when alkalinity is near 100 ppm.

⚠️ Muriatic Acid (31.45%)10 fl oz / 10k gal → lower pH by ~0.2 (at TA ≈ 100 ppm)

The pH (and alkalinity) reducer. Cheap and effective, but the most dangerous bottle on your shelf — the safety rules are not optional.

Protection (Stabilizer, Calcium, Salt)

☀️ Cyanuric Acid (Stabilizer)13 oz / 10k gal → raise Stabilizer 10 ppm

Sunscreen for your chlorine: without 30–50 ppm CYA, UV burns off outdoor-pool chlorine in hours. But it only goes up — dose carefully.

🪨 Calcium Chloride (77%)19.2 oz / 10k gal → raise Calcium Hardness 10 ppm

Protects plaster and equipment: water below ~200 ppm calcium is aggressive and pulls calcium out of plaster, grout and heat exchangers.

🧊 Pool Salt8.3 lb / 10k gal → raise Salt 100 ppm

For saltwater-generator pools: most cells want ~3,200 ppm. A typical 10,000-gallon fresh fill needs roughly 265 lb of salt to get there.