Add-On Filters for Your Present
Drinking Water System
Questions?
Call us at (940) 382-3814
Remove fluoride, nitrates, lead, sodium, arsenic, sediment, bacteria and other problem contaminants by making a simple addition to your current drinking water system. Add mineral content to your reverse osmosis unit's product water, or raise the pH.
You can add a dimension to your current water filter, or install an inexpensive specialty filter where no filter exists, by using the items provided on this page.
For example, if you have an undersink carbon block filter, you can add fluoride-removal capability to it by inserting our DI-AAL cartridge into your faucet line. And you can do it virtually without tools. Clip the faucet line and insert the ends into the quick connect fittings of our housing.
Or, if you have a reverse osmosis unit and would like to add a pH enhancing post filter, just insert our pH plus cartridge into the faucet line.
If you have a carbon block filter that becomes clogged with particulate, you can prolong its life by inserting an inexpensive sediment filter in front of it.
You can assure absolute bacteria-free and cyst-free performance from any existing filter by adding a ceramic cartridge after the filter.
The many possibilities include nitrate reduction, sodium reduction, softening, de-ionizing, lead and heavy metal removal, and you can greatly increase the life of any existing filter by adding to its chlorine/chemical-removal capacity.
(If you'd like to add a filter to your washing machine, see our Washer Filters.)
Add-On systems consist of three parts.
You'll need two of them, and the third is optional.1. A Filter Housing.
We recommend the flat-bottomed housing for ease of installation & service, but we provide a wall-mounted alternative. When ordering, specify 1/4" or 3/8"tube ports. Most undersink filters use either 1/4" or 3/8" tubing. The housing is equipped with John Guest quick connect fittings. They work best with plastic tubing, but they will adapt to copper. If you want an alternative compression fitting, please ask.
2. John Guest Plug-In Elbow Packet.
This is an optional item that allows you to make swiveling elbows of your straight fittings. It often makes installation much easier.
3. A Filter Cartridge.
Selected from the list below.
Basic Unit and Cartridges are sold separately. Standard shipping is UPS ground.
Freestanding
Flat-Bottomed Add-On unit
Please give tubing size — 1/4" or 3/8". The unit comes with straight John Guest quick-connect fittings that allow you to simply push the end of your present plastic tubing into the fitting.
Optional Plug-in elbows are available (see below), so that one or both fittings can be easily converted to an elbow if needed.
| Part # | Price | |
|---|---|---|
| AO200 | $31.00 | 
|
Bracket-mounted Add-On unit.
Part # : AO100
Bracket included. Please give tubing size—1/4" or 3/8". The unit comes with straight John Guest quick–connect fittings that allow you to simply push the end of your present plastic tubing into the fitting.
Optional Plug-in elbows are available (see below), so that one or both fittings can be easily converted to an elbow if needed.
| Part # | Price | |
|---|---|---|
| AO100 | $31.00 |
|
John Guest Plug-In Elbows
Quick Connect Fittings
Part # : JG022
These fittings quickly convert the standard "straight" fittings to swiveling elbows. We'll include either 3/8" or 1/4" to suit the unit you order. If ordering separately, please order from our complete John Guest List.
| Part # | Price | |
|---|---|---|
| JG022 | $2.75 |
|
Suggested Cartridges
Suggestions from among the many cartridges you can order for these units. Go to our Cartridge Menu for a full list. Any 9.75" X 2.5" cartridge will fit these add-on units.
| Part # | Description | Price | |
|---|---|---|---|
| FC010 |
Nitrate Removal Cartridge
Di-Tech's Nitrate removal cartridge. Can be regenerated with salt water. Removes 7500 ppm gallons (meaning, for example, if you have 10 parts per million nitrates in your water, you should change it at about 750 gallons). Contains high capacity anion exchange resin. |
$34.00 |
|
| FC103 |
5-Micron Sediment Cartridge
5-Micron Spun Poly Sediment Cartridge. Note: We have many sediment cartridges that will serve in this capacity. See the 9.75" X 2.5" size in our Cartridge Menu. |
$7.00 |
|
| FC704 |
Doulton Sterasyl
Ceramic with silver. Effective removal of bacteria and other pathogens. Very long life. Clean it annually (or as needed to restore flow) and it should last almost forever. |
$39.00 |
|
| FC708 |
Doulton Super Sterasyl Imperial
Doulton Imperial Super Sterasyl open end cartridge. Large diameter Super Sterasyl—ceramic/silver outer shell with granular carbon core for chemical reduction and taste/odor improvement. |
$68.00 |
|
| FC011 |
Fluoride Removal Cartridge
Fluoride Removal Cartridge. Approximately two years of fluoride removal from city tap water in undersink filters. This cartridge also removes arsenic, though capacity and duration vary greatly with water chemistry. |
$39.00 |
|
| FC008 |
KDF/Carbon Cartridge
Ditech GAC cartridge with 1.5 pounds of KDF redox medium added. Good Taste/Odor cartridge, with long term dechlorination and lead removal. Greatly enhances chlorine removal capacity. |
$39.00 |
|
| FC018 |
pH Increasing Cartridge
Pure Water Products all-calcite cartridge for raising low pH. B, D (should be followed by a second, carbon, post-filter). |
$22.00 |
|
| FC024 |
Softening Cartridge
Works like a miniature water softener. Can be regenerated with brine (salt water). |
$19.00 |
|
| FC004 |
Extruded Carbon Block with Cyst and Lead capability
MatriKX PB-1 extruded carbon block. Adds cyst removal, lead removal, and greater chemical capacity to your present undersink filter. This is one of many carbon block cartridges that can be added to your unit. See others here. |
$29.00 |
|
Site Index
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Filtration Systems
- Aeration for Iron & Sulfide
- Backwashing Filters
(whole house & well units)
- Chlorinators (Dry Pellet)
- Chlorinators (Feed Pumps)
- Countertop Water Filters
- Emergency Filters
- Garden Hose Filters
- Multi-Pure
- Reverse Osmosis, Residential
- Reverse Osmosis, Commercial
- Shower Filters
- Ultraviolet Systems
- Undersink Filters
- Water Softeners
- Whole House Filters
Parts & Cartridges
- Faucets
- Filter Media
- John Guest Fittings
- Membranes—Reverse Osmosis
- Replacement Cartridges
- Replacement Cartridges
(listed by part numbers)