Kohler Aquifer Single Cartridge (K-77685) review
By Daryna Klochko · Published · Specs checked Oct 15, 2026 · 
Scores 9.75/10, tied for 7th of the 32 under-sink filters we track. At $187.50 it costs less than the category median of $199.50. IAPMO lists it for Chlorine, Chloramine, Lead, Cysts, VOCs, PFOA/PFOS, one of 29 under-sink filters out of 32 with a certifier listing for a health claim. Its cartridge cost of about $165 a year is below the $168-a-year median of the 32 under-sink filters with a stated cartridge cost.
A long warranty: 5 years, tied for the longest stated among the 32 under-sink filters
- Price
- $187.50
- Certified for
- Lead · Cysts · VOCs +4
- Flow
- 0.85 gpm
- Cartridge life
- 389 gal
- Cost per year
- $165
- Warranty
- 5 years limited
Certification
Listed by IAPMO under NSF/ANSI 42 · 53 · 401 · P473 for Chlorine, Chloramine, Lead, Cysts, VOCs, PFOA/PFOS, checked Oct 15, 2026. Search the IAPMO listings
- Chlorine
- Chloramine
- Lead
- Cysts
- VOCs
- PFOA/PFOS
The contaminants or other substances removed or reduced by this water treatment device are not necessarily in your water. Listing checked on Oct 15, 2026. What a listing means and what it doesn't
Specs and sources
Checked Oct 15, 2026 · source under each valueFiltration
Cartridges and install
Buying
Warranty, returns and shipping
90 days from shipment (kohler.com, new and saleable).
Warranty: 5 years limited. Returns: 90 days from shipment (kohler.com, new and saleable). Shipping: not stated by the brand. Source: Kohler data sheet, checked Oct 15, 2026.
Source: Kohler data sheet, checked Oct 15, 2026.
Compared with similar under-sink filters
All 32 under-sink filters →| Model | Price | Certified for | Cost per year | Warranty | Score | Where to buy |
|---|---|---|---|---|---|---|
| Brio Premium 11" Under Sink Filter FUS100A11SS | $149.99 | Lead · Cysts +6 | $170 | 1 year (limited) | 9.5/10 | Check price → |
| Brondell Coral UC300 Three-Stage Under Sink | $179.99 | Lead · Cysts +8 | $80 | 1 year limited | 10/10 | Check price → |
| Kohler Aquifer Single Cartridge (K-77685)THIS MODEL | $187.50 | Lead · Cysts +5 | $165 | 5 years limited | 9.75/10 | Check price → |
| LARQ Advanced Under Sink Filter | $199 | PFAS · Chlorine | $198 | 1 year limited | 9.5/10 | Check price → |
| Hydroviv Under Sink Water Filter | $199.99 | Lead · Cysts +5 | $266 | 5 years | 9/10 | Check price → |
What owners say
Checked Oct 15, 2026Reviews only on the brand's own site. In our score this is 1.75 of 2 points. How we score
Store ratings change over time; the date shows when we checked.