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Aquifer® Water Filtration System
Filter Life
Replace the filter cartridges every 6 months, when the capacity has been exceeded, or when a noticeable decrease in water flow is observed.
Fluoride
Many water utilities add fluoride to their water for dental and skeletal health.
Aquifer filters do not remove fluoride.
Lead Reduction
Aquifer water filters are certified by NSF International to Standard NSF/ANSI 53 for the reduction of lead.
According to the standard, the maximum lead allowed through the filter is 0.010 mg/L.
Hexavalent Chromium Reduction
Aquifer filter cartridges do not reduce Hexavalent Chromium.
Select Pharmaceutical Removal
##K-77687 and K-77688
These water filters have been tested and certified by IAPMO R&T against NSF/ANSI Standard 401 for the reduction of select pharmaceuticals.
Select pharmaceuticals include: Phenytoin, Ibuprofen, Naproxen, Estrone, Bisphenol A, and Nonylphenol.
Flow Rates
K-77687 (Single Cartridge)
The flow rate of the single cartridge is 0.85 gal/min (3.2 l/min).
K-77688 (Two Cartridges)
The flow rate of the cartridges is 1.7 gal/min (6.4 l/min).
K-20852 (Replacement Cartridge)
The flow rate of the replacement cartridge is 1.39 gal/min (5.3 l/min).
Micron Rating
The micron rating for a fluid filter indicates the ability of the filter to remove contaminants by the size of particles it is exposed to.
The K-77687 and K-77688 Aquifer water filters have a Class I Particulate rating, which corresponds to a 0.5 micron rating.
The Class I test measures the filter's retention of particles between 0.5 and 1 micron, with the NSF requirement being greater than 85% to be in compliance.
Both the K-77687 and K-77688 filters have tested to 99.9% or greater.
Cartridge Material
K-77687 and K-77688
Aquifer filter cartridges are made of coconut shell-based carbon.
Recycling Old K-77687 and K-77688 Cartridges
When you replace a filter cartridge, invert the cartridge and let it drain for 3 days.
After 3 days, shake the cartridge to remove as much residual water as possible.
Place the cartridge in a plastic bag provided for this purpose, and completely seal the plastic bag.
Take the cartridge to your nearest FedEx shipping location.
The cartridge contents will be used as concrete fill for road and other concrete structures. The plastic housing will be recycled.
Cartridge Compatibility
The K-77687 and K-77688 filter cartridges are NOT compatible with the K-200 Aquifer water filtration system.
Order replacement filter cartridge K-20852 for your K-200 Aquifer system. Cartridge number K-20852 has replaced the K-201 and K-202 cartridges.
Replacing the K-201 and K-202 Filters with the K-20852 Filter
Replace filter cartridges every 6 months, when the capacity has been exceeded, or when a noticeable decrease in water flow is observed.
For more information about the Aquifer filtration system, visit kohler.com/filtration.
Remove the Existing Filter Cartridge
IMPORTANT! To avoid misalignment of the new filter, the old filter must be turned fully clockwise before removing from the filter head.
Position a bucket, pan, or rag under the filtration system to catch residual water.
Rotate the installed cartridge fully clockwise. Remove the filter cartridge.
Discard or recycle the use filter cartridge.
Prepare the New Filter Cartridge
Write the installation date on the label.
Remove and discard the cap from the new filter cartridge
Inspect the filter cartridge for damage.
Verify that both O-rings are present and positioned correctly in the grooves.
Install the New Filter Cartridge
IMPORTANT! The filter cartridge will only engage into the filter head one way. Do not force the components.
Align the filter cartridge with the filter head.
Press the filter cartridge upward, and use your hand to rotate the filter cartridge counterclockwise 90° to the locked position.
Turn ON the water supply.
Check the filter cartridge connections for leaks. Repair as needed.
Run water through the faucet for 5 minutes to remove any air and carbon particles from the system.