Designed to simplify hydroponics for everyone—at home, in education, commercially, and beyond—this guide provides simple starting ranges and practical tips. 

Aim for 5.5–6.5 for most vegetables and herbs.

• Check after mixing nutrients and regularly as plants grow.
• If adjustment is needed, add a little hydroponic pH Up or pH Down, mix, and test again.
• Use a calibrated pH meter or a test kit.

Start with 12–16 hours of grow-light exposure per day.

• Use a timer and provide a dark period each day.
• Follow the light manufacturer’s distance recommendations.
• Leafy greens generally need less intense light than fruiting plants such as tomatoes and peppers.
• Outdoors, choose a sunny location suited to the crop. Indoors, a window alone may not provide enough light.

Use fertilizer designed for hydroponics. NPK numbers describe the fertilizer’s nitrogen, phosphate, and potash percentages—not how much to add to the water.

• Leafy greens: An 8-15-36 hydroponic base fertilizer is one example formulated for lettuce. Follow the product’s instructions for other greens and herbs.
• Fruiting vegetables: A 4-18-38 hydroponic base fertilizer is one example used for tomatoes and peppers. It can also support leafy greens when mixed appropriately.
• Seedlings: Use the product’s seedling rate. Some formulas recommend half the established-plant rate until seedlings are well established.

Start with clean water suitable for growing food.

• Tap water often works, but its mineral content varies.
• Avoid sodium-softened water.
• Keep the reservoir covered to reduce algae and debris.
• Check levels regularly—large plants and hot weather use water faster.
• If problems persist, test the water rather than guessing.

About 65–75°F is a useful starting range for many leafy greens.

• Keep reservoirs out of direct sun and away from heat sources.
• Measure the water temperature, not just the room temperature.
• Warm water holds less oxygen, so watch submerged roots closely during hot weather.

About 65–75°F is a useful starting range for many common crops.

• Lettuce and spinach generally prefer cooler conditions.
• Basil, tomatoes, peppers, and cucumbers generally prefer warmer conditions.
• Choose plants that suit your growing space and season.
• Keep plants away from heating vents, cold drafts, and extreme heat.

Roots need access to both water and oxygen.

• Deep water culture: Use an air pump and air stone to oxygenate the water.
• Kratky: Leave an air gap as roots develop. Do not refill to the original level once air roots are established.
• Circulating or timed systems: Follow the system’s flow and watering instructions; check that pumps and drains work properly.
• Keep the plant’s stem and crown above the nutrient solution.

Leave room for mature plants and provide gentle airflow.

• Space plants for their full size, not their seedling size.
• Indoors, a small fan can help air move around leaves.
• Avoid strong airflow that dries plants out.
• If leaves stay wet or condensation builds up, improve ventilation.

Check the system regularly and clean between crops.

• Remove dead leaves and debris.
• Watch for pests, leaks, blocked tubing, and pump failures.
• Follow the system’s instructions for refreshing nutrient solution.
• Clean reusable equipment between plantings.
• For schools and shared spaces, assign someone to handle checks during weekends and breaks