Downey, CA tap water
Supplied by City of Downey, Utilities Division. Here's what its water means for your fish.
Disinfectant
Not confirmed
We couldn't confirm how your water is disinfected. US utilities use chlorine or chloramine, and chloramine doesn't gas off when water sits out.
Safety for fish and shrimp
Nitrate (NO₃)
1.6–21 ppm (Worth knowing)
Typical 14 ppm
Water changes can't take your tank's nitrate below this level.
Published by your utility: City of Downey, Utilities Division's 2025 water quality report.
Copper at home taps (first draw)
0.23–0.46 ppm (Worth knowing)
The 90th percentile of first-draw samples from homes: water that sat in household pipes for at least six hours.
Shrimp and snails are sensitive to copper. Water that sits in household pipes picks up the most; it drops once the tap has run for a minute.
Published by your utility: City of Downey, Utilities Division's 2025 water quality report.
Water chemistry
General hardness
169–308 ppm
Typical 264 ppm
Hard. Ideal for livebearers and African cichlids. Soft-water species may struggle to breed.
From California Water Board lab results, measured before treatment (2023–2026).
Carbonate hardness (alkalinity)
135–200 ppm
Typical 170 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results, measured before treatment (2023–2026).
pH
7–7.8
Typical 7.5
Most community fish do well here. Stable water matters more than the exact number.
Published by your utility: City of Downey, Utilities Division's 2025 water quality report.
Total dissolved solids
380–610 ppm
Typical 507 ppm
A rough measure of everything dissolved in the water. RO water reads near 0, so TDS is a quick way to compare waters.
Published by your utility: City of Downey, Utilities Division's 2025 water quality report.
Who supplies Downey, CA
- 2025 water quality report
City of Downey, Utilities Division
Serves all residents · Groundwater (wells) · Disinfectant not listed
Our data comes from public records and is still incomplete. Many utilities don't publish every number, so we're adding more all the time. Your city's range is a starting point: testing your own tap is the only way to know exactly what's in it.
Tap water lookup covers US cities only for now. Want to know why it matters? Read our story on tap water.
Compiled by Shoal & Stem from public records. Free to cite with a link.