Chlorine v Chloramine: What's the difference?

💧 Part of the Living Towers Water Guide
This guide is one of our complete collection of articles designed to help you choose the best water source, improve water quality, manage pH and nutrients, and keep your Tower Garden growing at its best.

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⚠️ Think Letting Your Water Sit Is Enough? Not Always. Here’s Why 💧🌱

If you’ve been growing hydroponically or aeroponically for a while, you’ve probably heard this advice:

“Just let your city water sit out for 24–48 hours and the chlorine will evaporate.”

And while that used to be solid advice… it’s no longer always true. 😬
Many cities have switched from chlorine to chloramine, and that changes everything for your plants.

Let’s break it down in plain English 👇


🚿 Chlorine vs. Chloramine: What’s the Difference?

🧪 Chlorine (the old-school disinfectant)

  • Added to city water to kill harmful bacteria

  • Evaporates naturally when water sits out

  • That’s why letting water rest for 24–48 hours used to work

🧬 Chloramine (the modern replacement)

  • A chemical bond of chlorine + ammonia

  • Much more stable than chlorine alone

  • Does NOT evaporate by letting water sit

  • Can remain in water for weeks

Chloramine vs. Chlorine

👉 If your city uses chloramine, leaving water out does nothing to remove it.


🏙️ Why Are Cities Switching to Chloramine?

Cities didn’t switch just to mess with gardeners 😅 — there are real reasons:

  • ✅ Longer-lasting disinfection throughout miles of pipes

  • ✅ Fewer harmful disinfection byproducts than chlorine alone

  • ✅ Better protection against bacteria in large municipal systems

  • ✅ More stable water quality from treatment plant to tap

From a drinking-water safety standpoint, chloramine makes sense.

From a plant-growing standpoint? 🚫 Not so much.


🌿 Why Chlorine & Chloramine Are a Problem for Hydroponic & Aeroponic Growing

Your plants aren’t just drinking water — they’re living in it.

In hydroponic and aeroponic systems, roots are constantly exposed to the water supply. That means anything in your water goes straight to the root zone.

🚫 These chemicals can:

  • Kill beneficial microbes that support root health

  • Stress or damage delicate root systems

  • Interfere with nutrient uptake

  • Slow growth and reduce yields

  • Cause mystery issues that look like nutrient deficiencies 😖

In soil gardening, organic matter can buffer some of this damage.
In hydroponics and aeroponics, there’s no buffer — the impact is immediate.


⏳ Why “Letting It Sit” Isn’t Reliable Anymore

Water Disinfectant Will Letting Water Sit Work?
Chlorine ✅ Yes
Chloramine ❌ No

If your city uses chloramine (and many do), your water may look fine, smell fine, and still be stressing your plants.


🚿 An Easy Solution: Filter Your Water First

The good news? You don’t have to guess or struggle with water quality.

We offer a GrowRite Garden Hose Filter that is specifically designed to remove BOTH chlorine and chloramine from city water — making it ideal for hydroponic and aeroponic growing.

🌱 Why a hose filter is a game‑changer:

  • ✅ Removes chlorine and chloramine

  • ✅ Helps protect delicate roots and beneficial microbes

  • ✅ Improves nutrient uptake and overall plant health

  • ✅ Easy to install — just connect it to your hose

  • ✅ Perfect for Tower Garden, Tower Farm, and other hydro systems

Instead of waiting days and hoping for the best, filtering your water ensures every fill starts with clean, plant‑friendly water.

👉 Check out the GrowRite Garden Hose Filter:


🌱 The Takeaway: Protect Your Roots

  • ✔️ Letting water sit only helps with chlorine

  • ❌ It does not remove chloramine

  • 🌿 Hydroponic & aeroponic plants are especially sensitive

  • 💧 Understanding your water source is just as important as nutrients

If you’re growing in a Tower Garden, Tower Farm, or any hydroponic system and struggling with unexplained plant issues, your water may be the missing piece of the puzzle.

✨ Healthy water = healthy roots = thriving plants ✨


Pro tip: Always check your city’s annual water quality report (CCR). It will clearly state whether chlorine or chloramine is used — and that knowledge alone can save you weeks of frustration and lost plants. 🌿

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