Use the HydroLogic Reverse Osmosis (RO) Water Filter ¼" OD (outer diameter) Black or Blue Tubing for micRO-75, Stealth-RO, or smallBoy to customize your indoor hydroponic garden. Use the HydroLogic Reverse Osmosis (RO) Water Filter ⅜" OD (outer diameter) Black or Blue Tubing for Evolution-RO or Merlin-Garden Pro to customize your indoor hydroponic garden.
