Command the pH. Unlock the grow. The pH Up/Down Bundle gives you instant, precise control when pH drifts — balancing your water and keeping your grow alive.
Adjusts pH up or down with clean, concentrated formulas
Works in soil, coco, hydro, DWC, aquaponics, and more
No dyes, additives, or sodium-based fillers
Safe for fruits, vegetables, ornamentals, and herbs
Made in the USA by real gardeners
$21.97
Nutrient lockout starts with a bad pH reading.
Even with the perfect feeding schedule, your plants can’t thrive if the pH is off. We won’t let you lose your grow. The Humboldts Secret pH Up/Down Bundle puts you back in control: one drop shifts the balance as needed, keeping roots open and protecting your yield.
"Cleaner and more consistent than baking soda. My pH stayed stable."
Clean formulas, real results:No dyes, no synthetic fillers, no clogging. Only phosphoric acid and potassium hydroxide, made for plants
All-in-one simplicity:You don’t have to guess which direction your pH will go. With both Up and Down on hand, you’re covered.
Safe for everything you grow:From hydro tomatoes to backyard herbs, these formulas are food-safe and fragrance-free.
Total pH control:Raise or lower your pH in seconds with targeted, highly concentrated solutions. Fewer drops, longer-lasting bottles.
Clean formulas, real results:No dyes, no synthetic fillers, no clogging. Only phosphoric acid and potassium hydroxide, made for plants
All-in-one simplicity:You don’t have to guess which direction your pH will go. With both Up and Down on hand, you’re covered.
Safe for everything you grow:From hydro tomatoes to backyard herbs, these formulas are food-safe and fragrance-free.
Total pH control:Raise or lower your pH in seconds with targeted, highly concentrated solutions. Fewer drops, longer-lasting bottles.
Command the chemistry — no advanced or stress alchemy required. pH Down: Made with high-purity phosphoric acid. Ideal for lowering pH in alkaline water or nutrient mixes. pH Up: Powered by commercial-grade potassium hydroxide (KOH). Raises pH cleanly without sodium buildup.
100% water-soluble
No synthetic dyes or additives
Works in all grow mediums
This bundle makes it easy to deal with acidic runoff, hard water, or nutrient drift.
Can I use this in hydroponics, aquaponics, or DWC systems?
Both pH Up and pH Down are fully water-soluble and safe for hydroponic systems including DWC, ebb and flow, and aquaponics. They dissolve cleanly without clogging lines, making them ideal for large reservoirs and small-scale indoor setups.
Is the pH Up/Down Bundle safe for vegetables, herbs, and fruiting plants?
Absolutely. Our formulas contain no dyes, fragrances, or preservatives, just high-purity acids and bases. They’re safe for use on leafy greens, tomatoes, citrus, herbs, and other edible crops. Ideal for both outdoor gardens and indoor houseplants.
How much should I use per gallon?
Start with 1 drop or 0.25–0.5 mL per gallon and retest. The formulas are highly concentrated, so small adjustments go a long way. Overcorrecting can stress your plants, always use a pH meter for accuracy.
What if I add too much pH Up or Down?
If you overshoot your target, simply use the opposite product to rebalance. For example, if your pH drops below 5.0, add pH Up gradually to return to the optimal range (5.5–6.5). Test after each adjustment.
Can I mix pH Up and Down in the same solution?
Never mix pH Up and pH Down directly. Always test your solution first and adjust in one direction only. Mixing the two can cause reactions that affect nutrient stability.
How long does the bundle last?
One bundle lasts through multiple grows for most users. Since you only need 1–2 mL per gallon, even daily hydro users find it lasts several months. So the pH Up/Down bundle is a cost-effective alternative to store-bought pH adjusters.
Does this work with well water, RO, or rainwater?
Yes. The bundle is effective across a range of water sources. Use pH Down for alkaline well water and pH Up to correct overly soft RO or rainwater that trends acidic. Regular test to make sure your solution stays in range.
Yes. Even balanced nutrient kits need a stable pH range to work effectively. Think of this bundle as your insurance policy against drift or unpredictable water sources. It keeps your feeding system optimized.
Master your pH. Maximize your grow.
Over one hundred thosuand gardeners trust Humboldts Secret formulas for a reason.
From rainwater-fed pots to full hydroponic systems, gardeners count on Humboldts Secret for clean nutrients and clear results. The pH Up/Down Bundle gives you power to harmonize your water and grow with confidence. .
