Easily convert any 3-stage reverse osmosis unit into a 4-stage RO/DI unit! AquaFX Add-On Deionization (DI) Filter installs last in line of your existing reverse osmosis (RO) unit to remove additional contaminants and dissolved solids. Color changing DI resin slowly turns rust red/orange when exhausted or at the end of its useful life for simple visual confirmation of filter performance.
AquaFX Add-On Deionization (DI) Filter is perfect for aquarium applications requiring pure water free of contaminants and dissolved solids. Use pure RO/DI water to mix synthetic salts for marine reef aquariums housing corals, anemones or other sensitive aquarium inhabitants. For applications demanding 18 megohm (ultra pure) water, the use of two DI units is strongly recommended. AquaFX Add-On Deionization (DI) Filter measures 4-1/2" dia x 11-1/2" high. Made in the USA.
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DI Filter Change Schedule
The Final Stage Deionization Polishing Filter
This filter consists of two resins. One is charged with Hydrogen (H+) and the other a Hydroxide ion (OH-). As water passes over these resins, the remaining "salts" (or ions) exchange out and only H+ and OH- are released into the stream. Due to the quality of resin we use, the water you get will be, literally as pure as possible. The resin is a color indicating resin; it will slowly change from a dark purple/blue/black to a rust red/orange color. As this filter nears the end of its useful life, you may experience "break though." The rate at which this happens is directly proportional to the quality of the source water feeding into the RO/DI unit.