Water Prep & Maintenance

Water: The Lifeblood of Hydroponics

In hydroponic systems, water is more than just a growing medium—it’s the lifeblood of your plants. As their sole source of food and nutrients, water plays an indispensable role in plant health and productivity. Just like humans, plants thrive on clean, well-balanced water, and providing the right quality can make all the difference in growth and resilience.

 

How Do You Ensure Clean, Optimal Water for Hydroponics?

 

With so many opinions circulating about water treatment, you’ve probably come across some... let’s just say interesting suggestions. But when it comes to hydroponics, science matters—not guesswork. That’s where experience comes in.

 

In this guide, we’ll walk you through a scientifically backed, field-tested approach to water preparation, built on three decades of hydroponic farming expertise.

 

No complicated jargon, no unnecessary steps—just a clear, effective method that any grower can follow, ensuring stable and healthy water for any reservoir-based hydroponic system.

 

Let’s dive in!

Choosing the Best Water Source for Hydroponics

Hydroponic home growers have several water sources to choose from, each with unique characteristics and implications for plant health. City water, or tap water, is commonly used due to its easy accessibility. However, it often contains chlorine and chloramine, which can be harmful to plants. City water typically has a moderate hardness level, meaning it contains a balanced amount of dissolved minerals like calcium and magnesium.

 

Well water on the other hand, can vary significantly in hardness depending on local geology. It often contains higher levels of minerals, making it "hard" water. Hard water can lead to nutrient imbalances in hydroponic systems, sometimes necessitating the use of a water softener to remove excess minerals. 

 

When a water softener is used, calcium and magnesium ions are typically replaced with sodium or potassium ions. While this softens the water and prevents mineral buildup, excessive sodium levels can be detrimental to certain plants, making it crucial to monitor and adjust nutrient solutions accordingly. 

 

Why Treated City Water Is the Best Choice  

In contrast, city water can be made ideal for hydroponic use with the right treatment. A high-quality water conditioner like PHLO neutralizes chlorine, chloramine, and even heavy metals, allowing tap water to be used directly without requiring a softener. This makes it a straightforward, affordable, and reliable choice for most home growers.

While some growers consider spring water as an alternative, it comes with its own challenges. Bottled spring water may be rich in natural minerals beneficial for plant growth, but it is often processed and expensive, making it impractical for consistent use in hydroponics. Additionally, its mineral content varies significantly, requiring careful monitoring and adjustments to nutrient solutions. 

 

For most home growers, the cost and inconsistency make spring water less practical compared to treated city or well water.  

 

Optimizing Water Quality for Hydroponics  

With the right approach, tap water can be transformed into a high-quality hydroponic solution that supports healthy plant growth. Using PHLO, growers can neutralize harmful contaminants, stabilize pH, and enhance water quality with beneficial minerals.

Curious about how PHLO can simplify your hydroponic setup? Stay tuned for more insights, or check it out in our shop! 

Filtration: A Useful but Not Mandatory Step in Hydroponics

While filtration can improve water quality for hydroponics, it’s not always a necessity beyond basic treatment. The key is balancing cleanliness with the preservation of essential minerals that plants need to thrive. Some filtration methods help remove harmful contaminants without stripping beneficial elements, making them a great option for home growers.

 

Types of Filtration: Practical Solutions for Home Growers

Two common filtration systems—under-the-sink filters and on-the-faucet filters—provide a simple and effective way to remove impurities while retaining the minerals necessary for healthy plant growth. These options offer cleaner water without requiring nutrient adjustments, making them a straightforward solution for hydroponic systems using city or well water.

 

Activated Charcoal Filtering: Affordable and Effective

Activated charcoal is a popular filtration choice among hydroponic growers due to its ability to adsorb chemicals, chlorine, and organic compounds. By reducing these impurities, activated charcoal enhances water quality and minimizes substances that could inhibit plant growth or cause damage over time.

This filtration method is cost-effective, easy to maintain, and doesn’t remove dissolved minerals—so it won’t affect water hardness or softness. If you're using city or well water that doesn’t require mineral adjustment, an activated charcoal filter can provide the purification needed without disrupting nutrient balance.

 

Reverse Osmosis (RO): Maximum Purification with Trade-offs

Reverse Osmosis (RO) offers a high level of purification, removing up to 99% of dissolved salts, minerals, and contaminants through a semi-permeable membrane. RO systems allow growers precise control over nutrient solutions, making them particularly useful for those who require absolute purity in their hydroponic setups.

 

However, RO filtration comes with trade-offs: 

  • Higher upfront cost and regular maintenance are required. 
  • It strips all minerals, making the water soft and completely neutral—which means growers must reintroduce calcium, magnesium, and other essential nutrients to maintain optimal plant health.

 

For those looking to minimize waste, tankless RO systems provide purification while dramatically reducing wastewater output, making them a more sustainable option.

 

Final Thoughts: What Works Best?

Filtration can be beneficial, but it’s not always required beyond basic treatment. The best approach depends on your specific water source and system needs. If your tap water is already balanced, a simple activated charcoal filter may be all you need. If you prefer complete control over your water composition, RO filtration can provide a clean slate—with the necessary nutrient adjustments afterward. 

 

With the right filtration strategy, you can create a stable water foundation that supports strong, healthy plants in any hydroponic setup.

 

Why Distilled Water Is NOT Ideal for Hydroponics

Distilled water is a bit of an outlier when it comes to water options—it doesn’t fall neatly into either the filtration or source categories. Unlike filtered tap or well water, which retains minerals, and natural sources like spring or city water, which contain varying compositions, distilled water is entirely stripped down. It’s not a naturally occurring source, nor is it a method of filtration designed to improve an existing water supply—it’s simply purified water with virtually nothing left in it.
 

While some might assume this makes it a perfect blank slate, distilled water actually presents significant challenges for hydroponic growers:

 

  • It lacks essential minerals—such as calcium and magnesium—that naturally help stabilize pH and support plant health.
  • It’s highly unstable—when exposed to air, it absorbs carbon dioxide, forming carbonic acid, which causes drastic pH fluctuations.
  • Nutrient management becomes harder—because hydroponic plants rely entirely on water for nutrients, starting with completely mineral-free water means growers must meticulously reintroduce everything artificially.

 

Instead of solving potential water issues, distilled water often creates new ones, making it harder to maintain nutrient balance and plant stability in a hydroponic system.

Nutrients: The Foundation of Hydroponic Success

We cannot stress this enough—nutrient quality is everything in hydroponic systems. Choosing low-cost, generic nutrients can lead to imbalances, deficiencies, and reduced yields. If your nutrients are purely agricultural-grade, you should be concerned about their lack of refinement for precision hydroponic growing. Be sure to review our guide on Nutrient Quality to understand why high-purity nutrients make all the difference.

 

Why Superior Nutrients Matter

When using a nutrient blend designed for both cannabis and agriculture, you gain access to a thoroughly tested, well-balanced formula that surpasses traditional agricultural-only products. Hydroponic growing demands precision, and not all nutrients are created equally. The right formulation ensures optimal uptake, consistent growth, and superior results across all plant types.

 

Veg+Bloom: The Ultimate All-in-One Hydroponic Nutrient

Veg+Bloom by Hydroponic Research is widely regarded as one of the best hydroponic nutrient solutions available. Its single-power formulation eliminates the need for switching between different powders for plants in different growth cycles, making it perfect for multi-crop, multi-stage hydroponic setups.

 

Unlike many nutrient mixes that require multiple separate products for various growth stages, Veg+Bloom provides complete nutrition from seedling to harvest—all in one product. This simplicity ensures that plants receive consistent and balanced feeding, removing the hassle of adjusting formulas throughout different plant cycles.

 

Additionally, Veg+Bloom offers precise blends tailored to different water systems: ✔ Hard water ✔ Soft water ✔ Reverse osmosis (RO) water ✔ Soil and peat systems

 

Be sure to select the blend that matches your water type to maximize effectiveness.

 

No More Guesswork: All Essential Nutrients Included

With Veg+Bloom, there’s no need for additional nutrients like Cal-Mag, as it already contains all the essential elements required for strong, healthy, and vigorous plant growth. This eliminates extra mixing, reduces errors, and optimizes absorption, making it a powerful yet hassle-free solution.

 

Veg+Bloom is the ONLY plant food we recommend and the ONLY plant food we use in our systems—because nothing else matches its purity, effectiveness, and ease of use.

 

Enhance Hydroponic Water Quality with VBX

In some cases, your water source may be minerally depleted—especially if you’re using RO water without a remineralizer. If this happens—or if you want to supercharge your plant nutrition right from the start—VBX is the solution.

 

VBX is the big brother to Veg+Bloom, offering even higher concentrations of calcium, magnesium, and essential nutrients. It’s specifically formulated for use with LED lighting, ensuring exceptional plant resilience and optimized growth rates—something that other nutrient brands simply don’t account for.

 

PHLO & Shine: The Finishing Touches for Pure, Balanced Growth

Beyond nutrient selection, water quality plays a critical role in hydroponics, and PHLO ensures that your water is neutralized, balanced, and free from contaminants, optimizing conditions for nutrient absorption.

Paired with Shine, a premium bloom booster, your plants receive enhanced metabolic support for bigger yields, stronger flowers, and healthier root development.

 

The Verdict: Why This Lineup Stands Above the Rest

✔ Single-power formulations—no need to switch powders for multi-crop, multi-stage plants. ✔ Highest purity available—ensuring optimal absorption and plant vitality. ✔ Complete nutrient balance—no need for additional supplements like Cal-Mag. ✔ Superior trace elements—formulated for precision hydroponic growing. ✔ Tailored water blends—hard water, soft water, RO, and soil systems accounted for. ✔ LED-ready solutions—ensuring maximum performance in modern hydroponic setups.

 

When it comes to hydroponic nutrition, there’s nothing that matches the quality and ease of Veg+Bloom, VBX, PHLO, and Shine. These high-purity formulations eliminate the guesswork, ensuring consistent, optimized growth without compromises.

 

Upgrade your system with the best nutrients available—and experience the difference for yourself.

Water Maintenance

Changing the water in your hydroponic system is crucial for maintaining a healthy and productive growing ​environment. Regular water changes help ensure that your plants receive a consistent supply of fresh nutrients, which ​can become depleted or imbalanced over time. This is particularly important because nutrient imbalances can lead to ​deficiencies or toxicities, both of which can harm plant growth. Additionally, water changes help prevent the buildup of ​harmful pathogens and algae, which can thrive in stagnant water and negatively impact plant health.

 

While it’s generally recommended to change the water every two to three weeks, the exact frequency can depend on ​factors such as the size of your system, the type of plants you’re growing, and their growth stage. Monitoring the ​electrical conductivity (EC) and pH levels of your nutrient solution can provide valuable insights into when a water ​change might be necessary. 

For instance, if you notice significant fluctuations in EC or pH that are difficult to correct, it ​might be time for a water change.

 

Neglecting regular water changes can lead to several issues. Nutrient imbalances can stunt plant growth or cause ​visible deficiencies, while the buildup of pathogens can lead to diseases that can quickly spread through your system. ​Algae growth can also become a problem, as it competes with your plants for nutrients and can clog your system. ​Therefore, maintaining a regular water change schedule is essential for the overall health and productivity of your ​hydroponic garden.

Equipment

Changing the water in your system doesn’t have to be a chore. There are tools that will make this task fast and efficient. ​Here is a video showing how fast a water change can be performed in a Gardyn system. However, this method can be ​uti​lized in any reservoir system.

Items Used in this Video

Conclusion

At UGrowFood, we recommend these methods for preparing water in a closed recirculating hydroponic system because they align with the true chemistry and biology of plants and water. We advise against adding any other substances to your water. Specific additives like Shine can be used at certain times to maximize flowering potential. However, additives like Cal-Mag are generally unnecessary in a Gardyn system if you are using the proper nutrients and managing your VPD correctly.

 

If you need more help, reach out to us in our Facebook Group or Telegram Group and consult with us live or with others that may be experiencing similar issues. 

 

The cornerstones of success include consistent environmental management, proper air circulation, and the ​management of nutrients and water quality. Performing regular water changes and top-off are crucial to the success of ​every hydroponic system. However, having the best nutrients or the cleanest water in the world won’t mean a thing if ​plants can’t use them. Make sure to review our guide on VPD to understand how your grow system’s environment is ​crucial.