pH Up + Down

pH up and down solutions bring a mixed feed back into the range your nutrient maker recommends, so roots can use what you mix. Pick the GH pH Control Kit for a tent, GH Pro pH or VPS for commercial fertigation, and Athena Balance when you buffer RO water.

23 products

pH Up + Down

pH Adjusters for Hydroponics and Soil

pH up and down solutions move a nutrient feed into the range each maker recommends for uptake. This collection carries General Hydroponics, Advanced Nutrients, Athena, Ventana Plant Science, HGV, Bluelab and X Nutrients. Liquids, dry powder and a test kit cover everything from a tent to commercial fertigation....

pH up and down infographic: mineral, non-mineral and dry adjusters, kits, target ranges and how to adjust a nutrient feed

Pair any adjuster with a calibrated meter from our pH testers and meters. Both sit in the wider nutrients range.

Types of pH Adjusters

Mineral pH Down and pH Up

General Hydroponics pH Down uses food-grade phosphoric acid. Its pH Up uses potassium hydroxide and potassium carbonate. Advanced Nutrients pH Up carries a 0-0-38 label because the hydroxide doubles as potash. Bluelab pH Up is 35% potassium hydroxide, and HGV Condition pH Up is 17%.

Commercial and Non-Mineral Adjusters

GH Pro pH adds no phosphorus, nitrogen, sulfate or potassium, and GH rates it at nearly three times its retail strength. VPS pH Up is 45% potassium hydroxide in 1, 5 and 55 gallon sizes. Athena Pro Balance is a dry pH up, mixed as a concentrate at a quarter to one pound per gallon.

Kits, Buffers and Mid-Strength Options

The GH pH Control Kit pairs 8 oz each of Up and Down with an indicator that reads 4.0 to 8.5. X Nutrients pH Up is mixed mid-strength, so each dose moves the reading a readable amount. Athena Balance buffers RO water, so the feed needs less adjusting after mixing.

How Growers Adjust pH

Mix base nutrients into fresh water first, then take a reading, because the feed moves pH on its way in. Add a small amount, stir, let it settle and retest. Advanced Nutrients targets 5.5 to 5.8 for hydro and 6.2 to 6.3 for sphagnum mixes. These are concentrated acids and bases, so wear goggles and gloves.

Frequently Asked Questions

What is pH up?

It is an alkaline solution that raises the pH of water or a nutrient feed. Most liquid pH Up is potassium hydroxide, sometimes with potassium carbonate, so it adds a little potassium. Advanced Nutrients pH Up carries a 0-0-38 label for that reason. GH Pro pH Up is the non-mineral option.

How much pH up per gallon?

There is no fixed figure, because the water's buffering decides how hard it resists change. General Hydroponics says to add a small amount, stir, test and repeat. X Nutrients suggests starting at 1 mL per gallon. Reverse osmosis water moves on very little, while hard tap water barely moves.

Can you use pH up and down for soil?

Yes, on the water or feed before it goes on. X Nutrients says to add pH Up to the water source rather than onto the medium. Advanced Nutrients targets 6.2 to 6.3 for sphagnum-based mixes and containers. Check runoff now and then to see how the medium is drifting.