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pH Control Kit - 4 Piece

pH Control Kit - 4 Piece

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The General Hydroponics® pH Test Indicator can help you maintain an ideal pH level (which is between 5.5 and 6.5). This can be achieved by monitoring your pH using the super concentrated drops found with the test indicator. Based on the test results, pH Up or pH down can be added to adjust the pH as needed. The General Hydroponics pH Test Indicator works across a wide pH spectrum (pH 4.0 – 8.5).

pH Control Kit Includes:

  • 8 oz. pH UP
  • 8 oz. pH DOWN
  • 1 oz. Indicator
  • Vial

The pH Control Kit provides a complete ecosystem for liquid-feed management. It allows growers to instantly measure their reservoir's pH spectrum (from 4.0 to 8.5) using a concentrated indicator solution, and then immediately correct the balance using premium pH Up (potassium hydroxide/carbonate) or pH Down (food-grade phosphoric acid) to ensure maximum nutrient availability.

Always mix your nutrients into fresh water completely before adjusting the pH. Fill the included test vial halfway with your mixed solution, add 3 drops of the pH Test Indicator, and observe the coloration against the chart. If the pH is too low, add a small, sparing amount of pH Up. If it is too high, add a small amount of pH Down. Stir thoroughly, re-test, and repeat until you hit the target 5.5–6.5 zone.

Even the most advanced nutrient recipe will fail if your reservoir's pH is out of range, locking out essential minerals and stalling plant growth. While digital meters are prone to drifting, losing calibration, and failing unexpectedly, this kit delivers fast, accurate, and easy-to-read results every single time—giving you a foolproof way to safeguard your plant's health.

Product guide

How to use this product

Review usage guidance, compatibility notes, and grower tips for this product.

Usage Guide

pH Control Kit — How to Use

  • Dose Slowly, Then Test: Add adjusting liquids sparingly to your mixed reservoir, stir thoroughly, and re-test. Small amounts go a long way.
  • Adjust After Nutrients: Never adjust undiluted nutrient concentrates. Mix your full nutrient lineup into fresh water first, then fine-tune with the kit.
  • The 3-Drop Rule: Use exactly 3 drops of indicator solution per halfway-filled vial (approx. 5ml) for an accurate color reading.

Grower Benefits

pH Control Kit — Key Benefits

  • Complete All-in-One Kit: Contains testing solution, adjustment liquids, and hardware in one box.
  • Fail-Safe Reliability: No batteries, no calibration required—works perfectly every time where digital pens fail.
  • Optimized Uptake: Ensures your plants stay in the 5.5–6.5 sweet spot for maximum mineral absorption.

Safety First

pH Control Kit — Resources & Safety

CAUTION: pH Down is corrosive and pH Up contains strong alkalis. Review the SDS before use; wear appropriate eye/skin protection and handle in a well-ventilated area. Keep out of reach of children. Store upright tightly sealed in a cool, dry place away from direct sunlight. Never mix undiluted pH Up and pH Down together.

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