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 20 lb. pail (2×10 lb. bags) is suited for mid-size operations with frequent high-pH correction needs.

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: 20 lb. (2×10 lb. bags in 3.5 gal. pail)
• Shipping: Ground shipping only — Limited quantity

Recommended Uses

• Building high-concentration pH-up stock solutions
• Aggressive pH correction in mid-size hydroponic and fertigation systems
• Commercial stock tank 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.