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.

Step 1
Serious

Root Rot (Pythium)

Symptoms

Roots turn brown, slimy, and may have a foul smell. Affected roots fall apart when touched. Plants wilt even though they are sitting in water. Growth stops and leaves yellow and droop. Can spread quickly to kill the entire plant if untreated.

Cause

Caused by the water-mold Pythium and related pathogens. Thrives in warm water (above 72F/22C), low dissolved oxygen, and stagnant conditions. Organic debris in the reservoir feeds the pathogen.

How to Fix
  1. Remove affected plants from the system and trim away all brown, slimy roots with sterile scissors
  2. Clean and sterilize the entire reservoir with hydrogen peroxide (3% solution, 3ml per liter). Wait 24-48 hours for the peroxide to fully dissipate before the next step
  3. After the peroxide has dissipated, add a beneficial bacteria product like Hydroguard or Great White to the fresh nutrient solution. Do NOT add beneficial bacteria at the same time as hydrogen peroxide, as the peroxide will kill them
  4. Lower water temperature to 65-68F/18-20C using a water chiller or frozen water bottles
  5. Increase aeration with additional air stones or a larger air pump
Prevention

Keep nutrient solution temperature between 65-72F (18-22C). Use adequate aeration with air stones. Keep the reservoir covered to block light and debris. Add beneficial bacteria preventatively. Clean the system between crops.

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Common Problems

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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.

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