Advanced Nutrients pH Down 0-55-0 Phosphoric Acid pH Adjuster

Bringing a High Reservoir Down with Advanced Nutrients pH Down

The base nutrients are in, the meter reads above target, and this is the bottle that pulls the number back. It is a liquid acid concentrate built on phosphoric acid, which makes up 60–80% of the formula by weight. Advanced Nutrients guarantees it at 55% available phosphate (P₂O₅), so the label reads 0-55-0. That phosphate is a nutrient the plant uses anyway, which is one reason phosphoric acid is the most common acid in hydroponic rooms. The concentrate itself sits at pH 1 and weighs just over 1.57 g/mL, about half again as heavy as water. Small additions move a reservoir quickly, and overshooting is the usual mistake. Advanced Nutrients sets the targets at 5.5 to 5.8 for hydroponic solutions and 6.2 to 6.3 for sphagnum-based mixes and plants in containers. There is no fixed dose on the label, because the amount depends on your water and your feed. Mix the nutrients into the water first, then read pH. Add a little with a syringe or pipette, stir well, let the solution settle and read again. The maker recommends a daily pH check and a fresh reservoir every week. Coco gets checked daily, while other substrates need attention two to four times a week.

Where a Phosphoric Acid pH Down Fits in a Grow Room

It works in every continuous liquid-feed setup Advanced Nutrients lists, from aeroponics and drip emitters to NFT, flood and drain and deep water culture. Coco, rockwool, sphagnum mixes and soil feed solutions take it the same way. In a tent, the 1 L bottle lives next to the meter and the measuring syringes. Commercial rooms dosing through an injector draw from the 23 L jug or the 208 L drum, plumbed into the acid line. Hard, high-alkalinity tap water goes through it faster, while RO water needs very little acid to land on target. Growers running pH Perfect base nutrients will reach for it rarely, since those lines hold pH on their own. Every addition also adds a little phosphorus to the feed. At adjustment doses that amount is minor, but rooms fighting very hard water should count it toward the total. Treat the concentrate with respect. The label warns of severe skin burns and eye damage, so wear chemical-resistant gloves and eye protection when pouring. Keep it away from bare metal fittings and metal measuring tools, because the acid corrodes metal. Store it upright and tightly capped in its original container, and never on the same shelf as pH Up.

Key Features

• 0-55-0 Guaranteed Analysis: Phosphoric acid supplies 55% available phosphate, so every adjustment also adds a nutrient the crop uses.
• High-Strength Concentrate: At 60–80% phosphoric acid, a few drops move a small reservoir, so a syringe gives the best control.
• Two pH Targets: Advanced Nutrients aims for 5.5 to 5.8 in hydroponics and 6.2 to 6.3 for sphagnum mixes and containers.
• Every Liquid-Feed System: Suits aeroponics, drip emitters, NFT, flood and drain and deep water culture without changes to the setup.
• Any Growing Media: Works in feed solutions for coco, rockwool, sphagnum mixes, hydroponic media and soil.
• Five Container Sizes: Runs from a 1 L bottle for tents up to a 208 L drum for injector-fed rooms.
• Corrosive Handling: Wear gloves and eye protection, keep it off bare metal, and store it apart from pH Up.

Technical Specifications