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Humboldts Secret CalMag & Iron, Liquid Plant Nutrient Fertilizer, 1 Gallon

Humboldts Secret CalMag & Iron, Liquid Plant Nutrient Fertilizer, 1 Gallon

Quantity
Regular price $73.55
Regular price Sale price $73.55
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  • Risk-Free 30-Day Returns
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30-Day Hassle-Free Returns

Not satisfied? Return your order within 30 days for a full refund or exchange — simple and easy.

✔ Easy return process

✔ Fast refunds

✔ No hidden conditions

Fast U.S. Shipping

We ship within the United States only — no international delays.

✔ Processing time: 1–2 business days

✔ Delivery time: 3–7 business days

✔ Real-time tracking available

👉 Track your order anytime from the header via Track Order

About This

  • Packaging Update: You may receive previous or updated packaging during our transition. Same formula, same performance. Strength for Every Stage - Humboldts Secret supplement with cal mag for plants delivers calcium, magnesium, and chelated iron to prevent deficiencies. It fortifies stems, improves leaf color, and supports flowering and fruiting plants for vigorous, healthy growth in any type of garden.
  • Fast-Acting Plant Recovery: Our balanced formula with calmag and chelated iron targets issues caused by nutrient imbalances, helping plants recover quickly. It boosts photosynthesis, nutrient transport, and root strength in vegetables, flowers, and herbs grown indoors or outdoors.
  • Maximum Absorption Power: Using our cal-mag for plants blend with added iron improves uptake efficiency, ensuring these essential minerals are fully utilized. It supports lush vegetative growth and abundant blooms, delivering consistent results for home or commercial growers.
  • Reliable Across All Setups: Humboldts Secret cal mag fertilizer with iron works in hydroponics, soil, and container gardens. It strengthens plant structure, enhances fruit quality, and ensures balanced nutrition in indoor and outdoor systems for dependable, healthy harvests.
  • Focused on Fruiting Success: Our formula with calcium and magnesium for plants plus chelated iron benefits crops in coco coir or reverse osmosis water. It helps prevent blossom end rot, promotes firm fruit set, and improves nutrient absorption for strong, productive plants in challenging conditions.

Overview

  • Brand : Humboldts Secret
  • Item Form : Liquid
  • Liquid Volume : 128 fluid ounces
  • Specific Uses For Product : Hydroponic
  • Global Trade Identification Number : 00648260730406
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Is Hard Water or Contaminated WaterDamaging Your Home?
Signs You May Be Experiencing Problems With Your Tap Water
Protect Your Home Appliances
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Softer Skin & Healthier Hair
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Pure, Better-Tasting Drinking Water
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Prevent Costly Hard Water Damage
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Reduce Limescale Buildup
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Clean Water, Whole Home
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Protect Your Home Appliances
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Softer Skin & Healthier Hair
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Pure, Better-Tasting Drinking Water
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Prevent Costly Hard Water Damage
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Reduce Limescale Buildup
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Clean Water, Whole Home
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RO Water Filters Reverse Osmosis Water Filters for Pure Drinking Water
Salt Water Softeners Salt Water Softeners for Powerful Hard Water Treatment
Pure Water. Better Living.

Experience the difference clean, softened water makes in your daily life — from healthier skin to better tasting drinking water.

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👉 Enjoy healthier skin and hair with every use.
Water Filter Cleaning Kits

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Under Sink Water Filters

👉 Softer, brighter clothes that last longer with every wash.

Reverse Osmosis Systems Best Reverse Osmosis Systems for Clean Drinking Water

See the Difference in Your Water — Instantly

Hard water, chlorine, and hidden contaminants can affect your health, skin, and appliances.

Our advanced filtration system removes impurities and delivers clean, safe water throughout your entire home.

Feel the difference in every drop — from your kitchen to your shower.

Impurity Reduction 95%
Chlorine Removal 99%

FAQ

Is installation difficult?
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No. Our systems are designed for easy DIY installation and most homeowners can install them without professional tools. If you need help, our support team is always available.
Do I need a plumber to install the system?
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No plumber is required. The system connects directly to your existing plumbing with simple fittings.
How does this system improve water quality?
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Our filtration system helps reduce common impurities and minerals that cause hard water problems, improving the taste and clarity of your water.
Will this help protect my appliances?
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Yes. Hard water minerals can build up inside appliances. Our system helps reduce scale buildup, helping extend the life of washing machines, dishwashers, and water heaters.
How often do filters need to be replaced?
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Most filters only need replacement every 6–12 months, depending on usage and local water conditions.
Will this improve my skin and hair?
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Many customers notice softer skin and smoother hair after switching to filtered or softened water.
What if I'm not satisfied with the system?
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If you're not completely satisfied, you can return your product within 30 days for a full refund.
Easy to install — no plumber required. Our experts are here if you need help.
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