At Josh's Plumbing, we believe that every family deserves clean, safe drinking water. That's why we're here to help you understand under-sink reverse osmosis (RO) systems—a popular and effective way to ensure the water you drink and cook with is free from harmful contaminants. In this article, we'll explain what reverse osmosis is, how it works, when you might need one, the differences between under-sink and whole-house systems, the truth about online sellers and branding, and why a remineralization stage is important for your health. Plus, we'll share how Josh's Plumbing can assist you with assessment, advice, and professional installation.

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What is a Reverse Osmosis System?

A reverse osmosis system is a water filtration method that uses a special filter called a membrane to remove impurities, contaminants, and dissolved solids from your water. It's one of the most effective ways to purify water, capable of removing up to 99% of harmful substances, including bacteria, viruses, heavy metals (like lead and arsenic), chemicals, and even some salts. Essentially, it turns your tap water into water that's as pure as possible, making it ideal for drinking and cooking.

The process works by reversing the natural flow of water through a semi-permeable membrane, which only allows water molecules to pass while blocking larger particles and contaminants. This technology is widely used in homes, restaurants, and even large-scale water treatment plants (Wikipedia).

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How Does It Work?

Under-sink reverse osmosis systems are installed beneath your kitchen sink and work through a simple but effective process:

1. Water Supply: The system connects to your cold water line under the sink.

2. Pre-Filtration: The water first passes through filters that remove large particles (like sand or rust) and chlorine, which can affect taste and odor. Common pre-filters include sediment filters and activated carbon filters.

3. Reverse Osmosis Filter: This is where the magic happens. The water is pushed through a very fine membrane. This membrane only lets water molecules through but blocks most contaminants.

4.  Storage Tank: The clean water is stored in a small tank under your sink until you need it. Some modern systems are tankless, providing water on demand. These systems require a power source under the sink to function are are not always practical.

5. Final Filter: The final stage is a carbon filter, to ensure the water tastes great and is free from any remaining odors.

6. Glass Filler: Reverse osmosis systems have a dedicated glass filler typically installed next to the kitchen faucet which is used for the pure water.

The result is fresh, great-tasting water straight from your tap, free from harmful substances. However, RO systems do produce some wastewater, typically 3–5 gallons for every gallon of purified water, which is flushed down the drain (EPA).

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When Do You Need One?

You might consider a reverse osmosis system if:

• Your tap water has high levels of dissolved solids or contaminants that standard filters can't remove, such as lead, arsenic, or nitrates (EWG).

• You want to ensure the water you drink and cook with is as pure as possible, reducing reliance on bottled water.

• You live in an area with known water quality issues, such as well water with high mineral content or municipal water with chemical residues.

• You prefer the convenience and cost savings of having purified water at home.

If you're unsure about your water quality, Josh's Plumbing can evaluate your water to determine if an RO system is the right solution for you.

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The Truth About Online Sellers and Branding

When shopping for reverse osmosis systems online, you might notice that many brands seem to offer similar products at different price points. The reality is that many of these systems use the same core components—like membranes, filters, and tanks—but are sold under different brand names. This means you might be paying more for marketing and branding rather than better technology.

For example:

• Membranes: The heart of the RO system, often sourced from the same manufacturers, perform similarly across brands.

• Filters: Sediment and carbon filters are standardized, with differences mainly in branding or minor design tweaks.

• Marketing: Some brands invest heavily in advertising, which increases the price without improving performance.

This “smoke and mirrors” can make it hard to choose the right system. Our recommendation is to focus on the stages of filtration and the rated throughput compared with your anticipated needs when selecting a system.

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Why is a Remineralizer Stage Important for Health?

While reverse osmosis is fantastic at removing harmful contaminants, it also removes beneficial minerals like calcium, magnesium, and potassium, which are essential for your health. These minerals support bone strength, muscle function, and heart health. Drinking water without them, especially if you rely heavily on RO water, could mean missing out on nutrients your body needs.

That’s where a remineralization stage comes in:

• What it does: A remineralizer adds healthy minerals back into the water, often using a special filter or cartridge that introduces calcium, magnesium, potassium, and other trace elements.

• Health benefits: Calcium and magnesium are crucial for strong bones and muscles, while potassium supports heart health. Remineralized water ensures you’re getting these nutrients, especially if your diet doesn’t provide enough (Pure Water Systems).

• Improved taste: RO water can taste flat or bland without minerals. Remineralization enhances the flavor, making it more enjoyable to drink (Gordon Water).

• Alkalinity: Some remineralizers raise the water’s pH, making it slightly alkaline, which some believe may offer additional health benefits, though this is debated.

In short, a remineralizer ensures you get the benefits of clean water without losing the good stuff your body needs. Many modern RO systems include this stage, and Josh’s Plumbing can help you choose one that does.

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How Josh's Plumbing Can Help

At Josh's Plumbing, we’re committed to helping you enjoy cleaner, safer water. Our services include:

• Assessment: We’ll work with you to determine if an RO system is necessary and which type suits your needs. This ensures you’re not spending money on a system you don’t need.

• Advice: We will guide you through the options, explaining the pros and cons of different systems and helping you avoid overpriced or overhyped products.

• Installation: We handle the installation professionally, ensuring your system is set up correctly and works efficiently from day one.

Whether you’re just curious about RO systems or ready to take the next step, we’re here to support you. Contact us today to learn more about how we can improve your home’s water quality.

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Conclusion

Understanding how under-sink reverse osmosis systems work is the first step toward ensuring your family has access to clean, safe drinking water. These systems are effective, affordable, and easy to maintain, making them a great choice for most homeowners. With Josh's Plumbing, you can trust that you’re getting expert advice and professional service every step of the way.

If you’re ready to improve your home’s water quality, contact Josh’s Plumbing today. We’re here to help you every step of the way, from assessing your needs to installing the perfect system for your home. Let us help you enjoy cleaner, healthier water right from your tap.