Nutrient lockout and salt build-up

Several 'deficiencies' at once that don't improve when you feed more. Usually pH out of range or salts building up in the medium.

Symptoms

• Several deficiency symptoms at once.
• Slow growth with no improvement when you feed more.
• Run-off EC much higher than the feed, or run-off pH well outside 5.5–6.5.
• White crust on the medium; drooping even though it's wet.

Quick checks

• Calibrate the pH pen.
• Measure run-off pH and EC and compare with what goes in.
• Look for crust on the medium surface.

How to fix it

1. 1
   Check

   Test the run-off

   Calibrate your pH pen, then test run-off pH and EC.

2. 2
   Physical

   Rinse the medium

   Rinse with plain water at the correct pH until run-off EC comes down. In hydro, change the tank and clean it.

3. 3
   Feed

   Restart at normal strength

   Go back to a normal-strength feed for the week at pH 5.5–6.5, with enough volume to get some run-off each time.

Likely causes

• Feed or medium pH out of range.
• A drifting or uncalibrated pH pen.
• Salt build-up from feeding without run-off.
• Hard water plus a strong feed.

What to avoid

• Don't keep adding more feed or extra supplements.
• Don't adjust pH before all nutrients are in the water.

Prevention

• Weekly run-off checks.
• Calibrate the pH pen at least monthly.
• Feed with some run-off each time.

Monkey products that can help

Grow A+B

Monkey say the bio-stimulants and bacteria in Part B of Grow (and Bloom) help release minerals and reduce salt build-up and lockout. They support a healthy plant but won't fix a pH problem.

Follow the growth chart: equal amounts of Part A and Part B, added to the water separately and never mixed together neat.

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Stress

Monkey say Stress improves uptake efficiency and reduces salt build-up in the medium, so it can help alongside correct pH.

2 ml per 10 L every week. Always add it to the water first and mix thoroughly before adding anything else.

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Products support a healthy plant. They don't replace fixing the cause.

When to get help

If run-off pH and EC are in line but the plant still shows multiple symptoms, check the roots, then email info@monkeynutrients.co.uk with your readings.

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