Master pH and EC/PPM management for hydroponics, coco, and soil. Learn optimal ranges, how to adjust, and how to avoid nutrient lockout.
Proper pH is critical for nutrient absorption. Hydroponic/coco: maintain 5.5-6.5 pH (ideal 5.8-6.2). Soil: maintain 6.0-7.0 pH (ideal 6.3-6.8). Test pH of your feed solution AFTER adding nutrients.
If pH drifts, use pH Up (potassium hydroxide) or pH Down (phosphoric acid) to adjust. Common signs of pH problems: yellowing leaves, brown spots, stunted growth. Always calibrate your pH meter monthly with buffer solutions.
EC (Electrical Conductivity) measures nutrient concentration. Seedlings: 0.4-0.8 EC (200-400 PPM). Veg: 1.0-1.6 EC (500-800 PPM). Early Bloom: 1.6-2.0 EC (800-1000 PPM). Peak Bloom: 2.0-2.6 EC (1000-1300 PPM).
Late Bloom/Flush: 0.0-0.4 EC (0-200 PPM). PPM conversion: EC × 500 (US scale) or EC × 700 (EU scale). Signs of overfeeding: burnt leaf tips, dark green leaves, claw-shaped leaves. Signs of underfeeding: pale/yellow leaves, slow growth, small leaves.
Plants need 3 macronutrients: Nitrogen (N) for leaf growth, Phosphorus (P) for roots/flowers, Potassium (K) for overall health. Plus secondary nutrients: Calcium, Magnesium, Sulfur. And micronutrients: Iron, Manganese, Zinc, etc.
Popular nutrient lines: Athena Pro Line (commercial powder), Fox Farm Trio (beginner-friendly liquid), General Hydroponics Flora Series (versatile 3-part), Jack's 3-2-1 (best value). Most growers also need Cal-Mag supplement, especially in coco or RO water. Follow the brand's feeding chart and start at 50-75% strength.
For hydroponics and coco, maintain pH 5.5-6.5 (ideal 5.8-6.2). For soil, maintain pH 6.0-7.0 (ideal 6.3-6.8). Always test pH AFTER adding nutrients to your water.
Nutrient lockout happens when pH drifts outside the optimal range, making nutrients chemically unavailable to roots even though they are present in solution. Symptoms include yellowing, browning, and stunted growth despite adequate feeding.
Seedlings: 0.4-0.8 EC (200-400 PPM). Veg: 1.0-1.6 EC (500-800 PPM). Early flower: 1.4-2.0 EC (700-1000 PPM). Mid-late flower: 1.8-2.4 EC (900-1200 PPM). Always watch plant response and adjust.