General Hydroponics® pH Down Liquid - 1 Gallon - Phosphoric Acid Formula

Reliable pH Down Adjustment — General Hydroponics pH Down Liquid, 1 Gallon

General Hydroponics pH Down Liquid is a widely used pH adjustment solution formulated to accurately lower the pH of hydroponic nutrient solutions and irrigation water. Formulated using food-grade phosphoric acid, this solution delivers consistent pH adjustment, a foundational tool for maintaining the 5.5-6.5 pH range that keeps nutrients available to plants. Available in a 1 Gallon size to match your operation's volume requirements.

Key Features & Benefits

• Phosphoric Acid Formula: Delivers effective pH reduction in nutrient solutions and water.
• Consistent Results: A widely used product line among hydroponic growers for repeatable pH adjustment performance.
• Easy Dosing: Add a small amount at a time when your nutrient pH is too high, mix thoroughly, and re-test before adding more.
• Prevents Nutrient Lockout: Keeping pH within 5.5-6.5 keeps macro and micronutrients soluble and bioavailable — pH drift causes lockout and deficiency symptoms.
• 1 Gallon Format: Sized to match the operation using it, from individual growers to larger commercial reservoirs.

Who Should Use This

Suitable for hydroponic growers of all experience levels, from hobby cultivators managing small systems to commercial facilities maintaining large nutrient reservoirs. Use alongside GH pH Up Liquid and the GH pH Test Indicator for complete pH management.

Compatibility

Compatible with all General Hydroponics nutrient programs and all hydroponic growing system types, including DWC, NFT, ebb and flow, drip, and recirculating systems. Use the GH pH Test Indicator or a calibrated digital meter to verify pH before and after adjustment.

About General Hydroponics

General Hydroponics (Santa Rosa, CA) is a Hawthorne Gardening Company brand, now under Vireo Growth, and pH Down Liquid is one of its foundational pH management products.

Frequently Asked Questions

What is the active ingredient in GH pH Down Liquid?

GH pH Down Liquid is formulated using food-grade phosphoric acid. That's the only active pH-adjusting ingredient in this formula.

How much should I add per adjustment?

Add small increments, typically starting around 1 mL per gallon, then mix thoroughly and re-test before adding more. The exact amount needed depends on your source water's buffering capacity and starting pH.

What is the target pH range for hydroponic systems?

Most hydroponic crops perform best with nutrient solution pH maintained between 5.5 and 6.5. This range keeps essential nutrients soluble and available for plant uptake.

When should I reach for the 1 Gallon size instead of a smaller bottle?

Choose the 1 Gallon size when your system volume or feeding frequency would otherwise mean frequent reordering of a smaller bottle. It's compatible with any hydroponic nutrient program regardless of size.