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RO Water System Replacement Filters, Kits & Accessories

Please note that these replacement cartridges are interchangeable with Captive Purity's, Kent Marine's, and SpectraPure's RO or RO/DI units. Marine Depot has researched the best replacement cartridges among these three manufacturers and offer only the best of each below.

Replacement Filter Kits

Item #DescriptionPrice 
RO2111RO Replacement Filter Kit$17.49
RO2113RO/DI Replacement Filter Kit$40.49
SP21131SpectraPure® MaxCap RO/DI Replacement Filter Kit$78.49 $58.89
SP344061SpectraPure® MaxCap Super DI and SilicaBuster Super DI Cartridge Kit$68.99

Sediment and Carbon Filters

Item #DescriptionPrice 
RO11310.5 Micron Carbon Block Replacement Filter for Captive Purity, SpectraPure & Kent Marine$13.49
RO11335 Micron Carbon Block Replacement Filter for Captive Purity and SpectraPure$10.49
RO1134Inline Carbon Filter - 1/4 inch FPT x 1/4 inch FPT$17.99
CP1511Captive Purity Chloramine Removal Carbon Block Filter Cartridge$20.99
AK01090AquaticLife Solid Carbon Block Pre-filter Reverse Osmosis Cartridge$10.49
AK01283AquaticLife KDF 85 / Catalytic GAC Cartridge$39.99
AK01250AquaticLife Replacement Carbon Cartridge for RO Buddie Reverse Osmosis System$9.99
RO11110.5 Micron Sediment Replacement Filter$12.99
RO1112Total Clarity 0.5 Micron Sediment Replacement Reverse Osmosis Filter Cartridge$7.49
RO11131 Micron Microtec Sediment Replacement Filter$3.99
SP2111SpectraPure® Zeta-Zorb 0.2 Micron Absolute Rate Sediment Cartridge$34.99
AK01249AquaticLife Replacement Sediment Cartridge for RO Buddie Reverse Osmosis System$7.99
AK01088AquaticLife 1 Micron Pre-Filter Reverse Osmosis Cartridge$9.49 $5.99

DI (Dionization) Cartridges

Item #DescriptionPrice 
SP2113SpectraPure® MaxCap DI Cartridge - Standard$29.99
SP2115SpectraPure® SilicaBuster Mixed Bed Multi Layer DI Cartridge$26.99
SP2117SpectraPure® SilicaBuster Color Indicating Mixed Bed Multi Layer DI Cartridge$26.99 $19.99
SP2119SpectraPure® Color Indicating Ammonia Removal DI Cartridge$26.99
SP34131SpectraPure® Mixed-Bed Color-Indicating Super DI Cartridge$29.99
SP34106SpectraPure® SilicaBuster Mixed Bed Super DI Cartridge$30.99
SP34406SpectraPure® MaxCap Super DI Cartridge$40.99
SP34706SpectraPure® SilicaBuster Super DI Cartridge$29.99
SP34726SpectraPure® SilicaBuster Color-Indicating Super DI Cartridge$29.99
RO1153Color Indicating Mixed Bed DI Cartridge$22.99
KM2117Kent Marine Hi-S DI Replacement Cartridge - Color Change$48.49 $39.99
AK01091AquaticLife Mixed Bed Resin Reverse Osmosis Cartridge$19.99
AK12427AquaticLife Color Changing Mixed Bed Resin DI Cartridge for RO Buddie Reverse Osmosis System - 21 cu. in.$24.99
CP1621Captive Purity Clear Refillable 10-Inch Cartridge for DI Resin$7.99
CP1623Captive Purity Bulk Deionization Resin - 1.25lb$11.99
CP1625Captive Purity Bulk Deionization Resin - 7.5lb$59.99
CP1627Captive Purity Bulk Color-Changing Deionization Resin - 1.25lb$12.99
CP1629Captive Purity Bulk Color-Changing Deionization Resin - 7.5lb$59.99

RO Membranes and Flow Restrictors

Item #DescriptionPrice 
SP5555SpectraPure® Standard 60-GPD TFC Membrane$41.99 $33.99
CP1811Captive Purity Hi-Silicate Removal TFC Replacement Membrane 25GPD$28.49
CP1813Captive Purity Hi-Silicate Removal TFC Replacement Membrane 35GPD$33.99
CP1815Captive Purity Hi-Silicate Removal TFC Replacement Membrane 50GPD$35.99
CP1819Captive Purity Hi-Silicate Removal TFC Replacement Membrane 75GPD$39.99
CP1823Captive Purity Hi-Silicate Removal TFC Replacement Membrane 150GPD$46.99
CP1821Captive Purity Hi-Silicate Removal TFC Replacement Membrane 100GPD$40.99
KM2241Kent Marine Hi-S TFC Membrane 35 GPD$95.49
KM2243Kent Marine Hi-S TFC Membrane 60 GPD$118.49
SP40030SpectraPure® SpectraSelect Plus 99% Rejection RO Membrane 90GPD$59.99
AK01092AquaticLife Replacement TFC Membrane 60 GPD$54.99
AK01084AquaticLife Replacement TFC Membrane 50 GPD$49.99
AK01093AquaticLife Replacement TFC Membrane 100 GPD$59.99
RO1210Flow Restrictor 25 GPD$3.49
RO1211Flow Restrictor 35 GPD$3.49
RO1213Flow Restrictor 50-60 GPD$3.99
RO1214Flow Restrictor 60 GPD$3.49
RO1215Flow Restrictor 75-100 GPD$3.99
RO1219Flow Restrictor 150 GPD$7.99

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Oct 14, 2014
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