Any aquarium owner looking to produce perfect water conditions for their fish and coral ought to get started with reverse osmosis water. The chlorine and chloramines that are poisonous to fish are totally absent from RO water, which also has a pH that is neutral and no water hardness. To flourish, many tropical fish need particular types of aquatic habitats, and RO systems can be your key to creating those conditions in your tank.
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Barracuda RODI Unit - Glacial 100 GPD (Chloramines Upgraded) - AquaFX
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RODI Filter FAQs
What’s the difference between RO and RODI?
RO (Reverse Osmosis) removes most contaminants, but not all. The DI (Deionization) stage polishes the water by removing remaining ions like nitrates, phosphates, and silicates — giving you 0 TDS water, ideal for reef tanks.
How do I know when to change the filters?
You’ll typically want to change sediment and carbon filters every 6 months. Use a TDS meter to monitor DI resin and RO membrane performance. When TDS rises above 0, it’s time to replace those stages.
Can I use well water with a RODI system?
Yes, but it depends on your well water's composition. High iron, sulfur, or sediment levels can clog filters quickly. You may need pre-filtration to protect the system and extend filter life.
What size RODI system should I get?
For most reef tanks, a 4-stage or 5-stage system is more than enough. Larger tanks or homes with poor tap water may benefit from the added filtration in a 5-stage setup.
Do I need to flush the system before using the water?
When first installing or after changing filters, yes. Flush the system for a few minutes to clear out dust and packing residue. After that, you can use the water as normal.
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