Plant Doctor
Diagnose and fix common hydroponic plant problems. No guesswork.
How It Works
Answer a few questions about what you are seeing and we will help you identify the problem and fix it. Click an option to move forward, or click any step in the trail above to go back.
Nitrogen Deficiency
Symptoms
Yellowing starts on older, lower leaves and moves upward. Leaves may become pale green before turning yellow and eventually falling off. Growth slows noticeably.
Cause
Insufficient nitrogen in the nutrient solution. This often happens when EC is too low, the nutrient solution is old and depleted, or pH is too high for proper nitrogen uptake.
How to Fix
- Check your EC/PPM and increase to the recommended range for your crop and growth stage
- Replace the nutrient solution if it is more than 2 weeks old
- Verify pH is in the 5.5-6.5 range for optimal nitrogen absorption
- If using a two-part nutrient, make sure you are adding equal amounts of both parts
Prevention
Monitor EC weekly and top off with fresh nutrient solution. Do a full solution change every 1-2 weeks. Use the Nutrient Calculator to get exact mixing amounts for your crop.
Common Problems
Jump directly to a diagnosis:
Prevention Tips
- Check pH every 1-2 days. Keep it between 5.5 and 6.5.
- Change nutrient solution completely every 1-2 weeks.
- Keep nutrient solution temperature between 65-72F (18-22C).
- Use adequate aeration. Size your air pump to at least 1 watt per gallon.
- Maintain good airflow around plants with fans.
- Clean and sanitize your system between crops.
- Inspect plants daily for early signs of problems.
- Top off with plain, pH-adjusted water between solution changes.
Nutrient Calculator
Get exact nutrient mixing amounts for your crop, growth stage, and brand.
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