Potassium hydroxide (KOH) flake, also known as caustic potash, is a high-purity dry pH-up agent used to raise pH in hydroponic and fertigation systems. With a minimum of 90% KOH and a fertilizer grade of 0-0-75, it delivers the highest potassium concentration of any common dry pH-up agent. The 1 lb. size is ideal for small-scale use, lab work, or first-time users evaluating KOH for stock solution preparation.

Why Potassium Hydroxide for pH Up?

KOH reacts rapidly and exothermically with water, making it highly effective for aggressive pH correction and building high-concentration stock solutions. Every dose contributes potassium — a primary macronutrient — directly to your nutrient solution.

Key Specifications

• Chemical Formula: KOH
• Fertilizer Grade: 0-0-75
• Minimum Purity: 90% KOH
• Form: Flake
• Solubility: Fully water soluble
• Production: Non-mercury cell process
• Net Weight: 1 lb.
• Shipping: Ground shipping only

Recommended Uses

• Building high-concentration pH-up stock solutions
• Aggressive pH correction in hydroponic and fertigation systems
• Small-scale trials and lab-scale nutrient solution preparation
• Aquaponic pH management

Application Notes

• Always add flake slowly to cold water — never add water to flake
• Reaction is exothermic — use heat-resistant containers
• Prepare as a stock concentrate; do not dose dry product directly into the reservoir
• Titrate in small increments and allow system to equilibrate before re-testing
• Full PPE required: nitrile gloves, safety glasses, and face shield

Safety

CORROSIVE — Hazardous Material. UN1813, Potassium hydroxide, solid, Class 8, PGII. Wear full PPE at all times. Store in a sealed container away from moisture and incompatible materials. Ground shipping only — not eligible for air freight.