Neptune Tap Water Purifier

The Neptune Tap Water Purifier is not a reverse osmosis system. It is a highly effective tap water filtration unit that removes harmful impurities, heavy metals, and toxins, producing excellent crystal clear deionized water for your aquarium.

This unit makes water safe to use in the aquarium without the need to purchase water conditioners and other chemical water treatments.  An excellent portable tap water filter for use in saltwater, coral reef, freshwater, including planted and discus, aquarium systems.  Saves time and money with its portability and efficient cartridge life.

The Neptune Tap Water Purifier attaches to the water source via a 3/4" adapter (garden hose size -- included) and produces 100% usable water without any waste water.  A faucet adapter can be purchased separately that hooks up to the included 3/4" adapter.  This unit comes complete with all the require tubing and cartridges.

The TWP unit focuses on the removal of the following impurities from tap water :


The deionization process strips the following from the water:

   Heavy Metals (Aluminum, Copper, Iron, Lead, Zinc)
   Dissolved Minerals (Lime, Sodium, Sulfates, Fluorides)


·       (#1) Inline GAC/KDF cartridge

·       (#2) Inline Coconut  Shell Carbon cartridge

·       (#3) AF Style MBR cartridge

·       6ft of tubing for both "Water In - white", Water Out - blue"

·       3/4" garden hose size adapter

Cartridge Replacement

    In order to produce quality water from your Neptune Tap Water Purifier at all times, it is recommended that you maintain a proper cartridge replacement schedule.  The frequency of cartridge replacement may vary depending on the water quality in your area.  Keep track of your Tap Water Purifier water quality output and maintain proper cartridge exchange regiments.

Guidelines for cartridge changes are as follows:

   (#1) Neptune Inline GAC/KDF
                -> every 1500 gallons or 6 months
   (#2) Neptune Inline Coconut Shell Carbon
                -> every 2000 gallons or 6 months
   (#3) Neptune AF style MBR
                -> every 5000 gallons or 6-8 months   

** The above values are approximate estimates and can vary due to location and incoming water conditions.  It is recommended to monitor unit parameters to maintain optimal quality.

When purchasing this unit NEW or when replacing cartridges, a system flush is required.  Follow the given diagrams to initially flush the system prior to collecting water for use in the aquarium.

Step 1:  (Refer to Diagram 1)
             Disconnect the red line going into the Coconut Shell Carbon (#2) cartridge in order to flush out
             GAC/KDF (#1) cartridge. Flush water though for approximately 5 minutes.

Step 2:  (Refer to Diagrams 2 and 3)
             Reconnect the red line to the (#2) cartridge and disconnect the red line leading into the
             "IN Port" of the Neptune AF Style MBR (#3) cartridge.  The (#3) cartridge is located within
             the large clear 10" canister at the base of the unit . Run water though to flush the (#2)
             cartridge for approximately 5 minutes.

Step 3:  (Refer to Diagram 3 and 4)
             Reconnect the red line to the "In Port" of the (#3) cartridge, and connect the blue line to
             the "Out Port" on the opposite end. Run water through for 5 minutes to flush out the
             (#3) cartridge.

Step 4:  (Refer to Main Diagram)
            Your system should now be ready to collect water.  The product water will now come out
            from the blue line. It should look similar to that of the Main Diagram with all lines in place.                            
NEPTUNE Tap Water Purifier
Neptune Tap Water Purifier  :   $109.99
Reverse Osmosis Quality Water
without the waste of an R/O unit !!
Frequently Asked Questions

Why has my DI Resin changed color right away?
You must first flush the system when a new GAC/KDF cartridge is installed.  If the GAC/KDF cartridge is not initially flushed properly, the inline sediment cartridge will clog up faster, and the resin cartridge will be used up more quickly.
NOTE: If the resin color has changed quickly, you may still continue using it, but test the water with a TDS (total dissolved solids) meter to check the quality.

Can I disconnect the system and reconnect it later on?
Yes. You may make the desired amount of water that you need, and then disconnect the system from the water supply for use later on.

Can I use this on a well system?
Yes.  This filter can be used on a well supply.  However, the cartridges may be exhausted faster that normal.  For well water, we suggest our Neptune Well Water purifier or one of the Neptune line of RO / DI systems.

Can I use this filter with a float valve?
Yes.  The OUT Port (blue line) can be connected to a float valve to produce water automatically.
You may purchase an adjustable float valve here on our website.

If your problem was not addressed by these FAQ's, please contact us.
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