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Captive Purity Reverse Osmosis (RO Water) & Reverse Osmosis/Deionization units (RO/DI Water) Systems

Captive Purity represents the highest quality in reverse osmosis technology. Captive Purity Reverse Osmosis Sytems meet stringent standards and far exceeds the quality of systems from other manufacturers. A wide variety of options ranging from economy 2-stage units to top of the line 4-stage RO/DI are available to suit your exact needs. Drinking water systems and custom installation solutions are available. Captive Purity Reverse Osmosis Systems are engineered and manufactured under strict guidelines to produce extremely pure water with exceptional focus on minimizing phosphates and silicates. This is a very important feature for reef aquariums.
  • Remove over 98% of all ionic impurities.
  • Remove over 95-96% of organic impurities.
  • Remove colloidal and particulate impurities.
  • Remove micro-organisms and pyrogens.
  • Remove chlorine, chloramines, pesticides, etc.
2-Stage Compact RO Water Systems
2-stage Compact Reverse Osmosis (RO) System
  • Ultracompact and economical reverse osmosis system.
  • 1500 gallon chlorine removal capacity sediment/carbon combo inline prefilter.
  • High flow and rejection TFC membrane
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.
Item #DescriptionPrice 
CP1111Captive Purity 35 GPD Compact RO$84.99
3-Stage Deluxe RO Water Systems
3-Stage Deluxe Reverse Osmosis (RO) System
  • 1 micron sediment prefilter.
  • 5 micron carbon prefilter.
  • High flow and rejection TFC membrane.
  • Available in white or clear.
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.
Item #DescriptionPrice 
CP1121Captive Purity 35 GPD Deluxe RO Filter System - White Canisters$118.99
CP1123Captive Purity 75 GPD Deluxe RO Filter System - White Canisters$140.49
CP1131Captive Purity 35 GPD Deluxe RO Filter System - Clear Canisters$128.49
CP1133Captive Purity 75 GPD Deluxe RO Filter System - Clear Canisters$185.99
CP1911Captive Purity Replacement O-Ring for RO Filter System$2.49
3-Stage Pro RO Water Systems
3-Stage Pro Reverse Osmosis (RO) System
  • 1 micron sediment prefilter.
  • Very high efficiency 0.5 micron carbon prefilter
  • High silica and phosphate rejection TFC membrane.
  • Pressure guage for easy monitoring.
  • Quick connect and disconnect John Guest Super Speedfit fittings.
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.
Item #DescriptionPrice 
CP1143Captive Purity 75 GPD Pro RO Filter System - Clear Canisters$189.99
CP1911Captive Purity Replacement O-Ring for RO Filter System$2.49
4-stage Deluxe RO/DI Water Systems
4-Sage Deluxe Reverse Osmosis / Deionization (RO/DI) System  
  • 1 micron sediment prefilter.
  • 5 micron carbon prefilter.
  • High flow and rejection TFC membrane.
  • Color Change DI cartridge for easy monitoring and maintenance
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.
Item #DescriptionPrice 
CP1331Captive Purity 35 GPD Deluxe RO/DI Filter System - Clear Canisters$160.49
CP1333Captive Purity 75 GPD Deluxe RO/DI Filter System - Clear Canisters$176.99
CP1911Captive Purity Replacement O-Ring for RO Filter System$2.49
4-stage Pro RO/DI Water Systems
4-Stage Pro Reverse Osmosis / Deionization (RO/DI) System  
  • 1 micron sediment prefilter.
  • Very high efficiency 0.5 micron carbon prefilter
  • High silica and phosphate rejection TFC membrane.
  • Pressure guage for easy monitoring.
  • Quick connect and disconnect John Guest Super Speedfit fittings.
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
Note: A flush valve can significantly enhance the life of TFC membrane by flushing out any harmful impurity from the membrane.
Item #DescriptionPrice 
CP1341Captive Purity 35 GPD Pro RO/DI Filter System - Clear Canisters$220.99
CP1343Captive Purity 75 GPD Pro RO/DI Filter System - Clear Canisters$252.49
CP1911Captive Purity Replacement O-Ring for RO Filter System$2.49
4-stage Pro Power RO/DI Water Systems
4-stage Pro Power RO/DI Water Systems Captive Purity represents the highest quality in reverse osmosis technology. Captive Purity Reverse Osmosis Systems meet stringent standards and far exceeds the quality of systems from other manufacturers. A wide variety of options ranging from economy 2-Stage RO units to top of the line 5-Stage Powered RO/DI units are available to suit your exact needs.

The 5-Stage Powered RO/DI is great for larger aquariums, for households with low water pressure, or for hobbyists that desire the purest water possible.

Drinking water systems and custom installation solutions are available. Captive Purity Reverse Osmosis Systems are engineered and manufactured under strict guidelines to produce extremely pure water with exceptional focus on minimizing phosphates and silicates. This is a very important feature for reef aquariums.
  • Remove over 98% of all ionic impurities.
  • Remove over 95-96% of organic impurities.
  • Remove colloidal and particulate impurities.
  • Remove micro-organisms and pyrogens.
  • Remove chlorine, chloramines, pesticides, etc.
  • All systems include a non-corrosive 3/4" plastic garden hose adapter (non-brass).
100GPD 5-Stage Pro Powered RO/DI System Features:
  • 1 micron sediment prefilter.
  • Very high efficiency 0.5 micron carbon prefilter
  • High silica and phosphate rejection TFC membrane.
  • Two electronic purity monitors for easy monitoring.
  • Powered booster pump to maximize output and efficiency (1:1 Product-to-Waste Water Ratio)
  • High and low pressure safety switches
  • Quick connect and disconnect fittings.
  • Two multi-resin high silica, phosphate, and nitrate absorption DI cartridges for ultra-pure water.
  • Includes non-corrosive 3/4" plastic garden hose adapter (non-brass).
  • The Captive Purity 5-stage Pro Powered RO/DI is a titan among water purification systems offering unparalleled performance in both craftsmanship and water purity.
  • Clear Canisters.
Item #DescriptionPrice 
CP1355Captive Purity 100 GPD Pro Power RO/DI Filter System - Clear Canisters$409.99
Single Deionization Canister Add-On Kit
Single Deionization Canister A quick and easy way to add De-Ionization to any RO system or to add a secondary DI stage to any RO/DI system.

  • Produce pure RO/DI water for your aquarium to reduce nuisance algae growth
  • Available with or without a TDS meter to monitor your DI cartridge
  • Includes filter wrench and 6 ft of tubing
  • Inline pressure reducer included to ensure optimal flow through the canister
Item #DescriptionPrice 
CP1611Captive Purity Single Deionization Canister with TDS Meter$69.99
CP1613Captive Purity Single Deionization Canister$43.49

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