Reverse Osmosis Water for Aquariums: Essential or Overrated?

If you’ve spent some time on aquarium hobbyists’ forums around the Internet, you’d likely come across someone recommending Reverse Osmosis water (RO) while others say it isn’t necessary.

Reverse osmosis water isn’t for everybody, that’s for sure.

What is it, anyway? Simply put, RO water is highly purified water with most everything else removed. It’s a popular choice for creating specific water conditions in tanks.

But do we really need it? Let’s find out.

Benefits of RO Water

RO water's like a blank canvas. It gives you total control over what goes in your tank. Here's why that matters:

RO water allows you to create the perfect environment for your fish and plants by providing a blank slate. Since it removes most impurities, you can add minerals and adjust the water chemistry to meet the specific needs of your aquarium inhabitants.

For example, if you're keeping nanofish like Neon Tetras, Cardinal Tetras, or Celestial Pearl Danios, which prefer softer, acidic water, you can easily achieve these conditions with RO water.

Keeping fish in their preferred parameters will help in overall tank health. It also helps in preventing algae growth and diseases.

By eliminating contaminants like phosphates and silicates, which often fuel algae blooms, you can maintain a cleaner, healthier tank. Also, fewer impurities mean less stress on your fish, reducing the risk of illness.

Another benefit is the precise control over water parameters. RO water allows you to set and maintain the exact pH, hardness, and other key factors for your aquarium.

This level of control is especially useful for sensitive species like Dwarf Shrimp, rams, or killifish, as stable conditions are crucial for their well-being.

When you can adjust precise parameters, breeding might be more successful as well.

With RO water, you're equipped to provide the best possible environment for your aquatic pets.

Is RO Water Necessary?

It all depends on several factors. These include the type of fish you're keeping, the kind of aquarium you have, and the quality of your tap water.

For aquarists keeping sensitive fish species or maintaining reef tanks, RO water can be a lifesaver. Sensitive species like Discus, Crystal Red Shrimp, or Ram Cichlids require specific water conditions that tap water might not provide.

Reef tanks, with their delicate corals and invertebrates, also benefit greatly from the purity of RO water, as it allows for precise control over parameters like calcium and alkalinity.

Additionally, if your tap water has a high Total Dissolved Solids (TDS) level, RO water can help reduce these impurities, creating a more stable environment for your fish.

However, RO water might be overkill for low-maintenance tanks or hardy fish species. For example, Guppies, Platies, and Bettas can thrive in a wide range of water conditions and typically don't require the level of purity that RO water offers.

In such cases, using simple water conditioners or dechlorinators might be sufficient to make tap water safe for your aquarium. Bottom line: test your tap water, research your fish, and decide based on that.

RO water's a tool, not a requirement for every tank.

Alternatives to RO Water

If RO water isn't practical (RO doesn't come out of municipal taps, afterall) or necessary for your aquarium, there are other options to consider. These alternatives can help you maintain a healthy environment for your fish without the need for an RO system.

Dechlorinators and Water Conditioners

These are essential tools for any aquarium enthusiast. Dechlorinators remove harmful chlorine and chloramine from tap water, making it safe for fish. Water conditioners go a step further by neutralizing heavy metals and detoxifying ammonia.

They're easy to use—just add the recommended amount to your tap water before adding it to your tank.

Distilled Water

While not as pure as RO water, distilled water is a good alternative for topping off tanks, especially when you need to avoid adding minerals. It’s free from most impurities but lacks essential minerals that fish and plants need.

You'll need to remineralize it to make it suitable for your aquarium.

You can get distilled water at those filling station kiosks at most bigger grocery stores. They are around $.50 to $1 a gallon.

Well Water

Using well water can be an option, but be careful. Unlike municipal water, well water isn't treated. It might contain minerals, metals, or other contaminants. Test the well water thoroughly before using it in your aquarium.

Keep in mind that well water quality can vary significantly, so regular testing is advised. If the water is high in minerals or has an unusual pH, you might still need a filtration system to make it suitable for your fish.

Remember, the goal is clean, stable water. How you get there depends on your specific situation.

Takeaway

So, is RO water essential or overrated? Well, it's not black and white. Admittedly, RO water can be a game-changer for sensitive species and reef tanks. But for most freshwater setups, good old tap water works just fine.

The key is knowing your tank's needs. Test your tap water, research your fish, and make an informed decision. RO water's a powerful tool, but it's not always necessary. It all comes down to what works best for your tank and its inhabitants.