Description
sera Flore CO2 Reactor 500
The sera flore CO2 active reactor 500 is an “active” CO2 reactor designed for freshwater aquariums. Unlike passive diffusers that rely on gas pressure to push bubbles through a ceramic disc, this unit uses the mechanical force of moving water to churn and dissolve CO2 completely. Recommended for aquariums between 250L and 600L.
Features:
- Twin Rotor System: Features a double rotor design; the upper “lamella” rotor breaks CO2 bubbles into micro-bubbles while the lower rotor mixes them into the water stream.
- Smoky Gray Color: The dark plastic housing is specifically designed to inhibit algae growth inside the reactor, keeping the rotors spinning smoothly.
- Standard Connectors: Includes hose connectors with union nuts for secure fastening (usually compatible with standard 16/22mm or 12/16mm hoses depending on your plumbing).
- Fine Mist Technology: Designed to ensure no large gas bubbles escape back into the aquarium, maximizing the value of your CO2 gas.
Benefits:
- High Efficiency: Because it dissolves CO2 completely, you waste less gas compared to traditional diffusers where bubbles often reach the surface and pop.
- Clutter-Free Tank: By installing it inline with your external filter, you remove bulky equipment (like ladders or large diffusers) from the visual area of the tank.
- Stability: Active mixing ensures a more consistent CO2 concentration throughout the water column, which is vital for preventing algae and promoting lush plant growth.
- Easy Maintenance: The unit can be entirely disassembled for cleaning without needing specialized tools.
- Dimensions: Approximately 23cm (9″) tall
Tips:
- Check Valve is Critical: Always use a high-quality CO2 check valve between the reactor and your solenoid. If the pump stops, water can siphon back into your regulator and ruin it.
- Flow Matters: Ensure your pump or filter meets the 500 L/h minimum. If the flow is too weak, the rotors won’t spin fast enough to dissolve the gas, leading to “gas lock” where a large bubble builds up at the top.
- Vertical Mounting: For best results, mount the reactor perfectly vertical. This ensures the CO2 trap at the top functions correctly and the rotors don’t rattle against the sides.
- Burping the Air: After initial installation, you may hear a “sloshing” noise. This is usually trapped air. Tilting the unit slightly while the water is running can help purge the air until only CO2 remains.
- Regular Cleaning: If you notice the rotors slowing down or becoming noisy, it’s time to disassemble and clean the internal shafts. Organic biofilm can eventually create drag on the moving parts.

