Reverse Osmosis: Turning Tap Water into Gold

Reverse osmosis water is an incredible starting point for any aquarium owner seeking to create ideal water conditions for any and all inhabitants of their tanks. But what even is RO water and why is it so beneficial to both you and your aquarium? Let's find out together in this video while walking through how to easily install the BRS RO only 4-Stage Filtration system right in your kitchen sink.

Beginner friendly!

Reverse Osmosis Water in Aquariums FAQs

Q: What does RO stand for?
A: RO stands for Reverse Osmosis.

Q: What is RO water?
A: RO water is water that has been purified by forcing it through specialized membranes and filters that remove contaminants, chemicals, and dissolved solids.

Q: What is the difference between RO and RODI water?
A: RO water is highly purified but may still contain small amounts of dissolved solids. RODI water adds a deionization (DI) stage that removes the remaining trace contaminants, producing ultra-pure water.

Q: Why is RO or RODI water beneficial for aquariums?
A: RO & RODI water give you complete control. It acts as a blank slate that isn’t influenced by your local water supply, allowing you to build ideal water conditions for your fish or coral. 

Q: Which is better for aquariums: RO or RODI?
A: Both are far superior to tap water. RO water is an excellent starting point for most freshwater aquariums, while RODI is ideal for sensitive species, soft-water tanks, breeding setups, and reef aquariums.

Q: Why is RO or RODI better than conditioned tap water?
A: Water conditioners neutralize chlorine and chloramine but don’t remove heavy metals, nutrients, or other dissolved contaminants. RO and RODI physically remove these substances.

Q: What does a 4-stage RO system do?
A: A 4-stage RO system filters water through multiple layers to remove sediment, chlorine, and dissolved contaminants before producing purified water.

Q: What does the DI stage add to an RO system?
A: The DI stage removes the last traces of minerals and dissolved solids that pass through the RO membrane, producing laboratory-grade pure water.

Q: Can RO or RODI systems be installed on a kitchen sink?
A: Yes. Many systems include faucet diverters and adapters for quick, temporary kitchen sink installations.

Q: Is installing an RO or RODI system difficult?
A: Installation can feel intimidating at first, but most hobbyists find it straightforward and much easier than expected after setup.

Q: What is a float valve and why should I use one?
A: A float valve automatically shuts off the system when the water reaches a certain level, preventing overflows.

Q: Is RO or RODI water neutral?
A: Yes. Both RO and RODI water are neutral in pH and contain no hardness or buffering capacity unless minerals are intentionally added back.

Q: Do I need to remineralize RO or RODI water?
A: For most freshwater fish, yes. Minerals should be added back to match the species’ natural habitat and ensure healthy biological function.

Q: Can RO systems be upgraded later?
A: Absolutely. RO systems are modular and can be expanded with additional filters, DI stages, or dedicated faucets.

Q: Is RO water only useful for aquariums?
A: No. Many hobbyists install RO systems for everyday drinking water because of its purity and consistency.

Q: Is RO water better than buying distilled water?
A: Yes. An RO system is more convenient, cost-effective long term, and eliminates frequent trips to grocery stores or fish stores.

Q: Who should consider RO vs RODI?
A: RO is perfect for most freshwater aquariums, while RODI is best for advanced freshwater setups, breeding projects, and all saltwater or reef aquariums.