Oxnard, CA tap water
Supplied mostly by United Wtr Cons Dist, plus 1 other utility. Here's what the water means for your fish.
Disinfectant
Chloramine
Your water is treated with chloramine. Unlike chlorine, it doesn't gas off when water sits out, and many pitcher and fridge filters aren't rated to remove it. Conditioners that list chloramine on the label break it apart, which frees about 0.38 ppm of ammonia here. Some utilities switch to plain chlorine for a few weeks a year.
Safety for fish and shrimp
Ammonia (with conditioner)
Estimate0.05–0.63 ppm (Low)
Typical 0.38 ppm
This is what a conditioner frees when it breaks the chloramine apart. A cycled filter clears it within a day.
Estimated from the chloramine level City of Oxnard Water Division reports (2024).
Nitrite (NO₂)
Not detected (Low)
Not detected in testing, so any nitrite in your tank comes from the tank itself.
From California Water Board lab results (2023–2026).
Nitrate (NO₃)
6.6–15 ppm (Worth knowing)
Typical 12 ppm
Water changes can't take your tank's nitrate below this level.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
Copper at home taps
Up to 0.79 ppm (Low)
Typically not detected
Not detected in testing. Water that sits in household pipes overnight can still pick some up.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
Chlorine or chloramine at the tap
0.2–2.6 ppm
Typical 1.6 ppm
At tap levels, chlorine and chloramine are toxic to fish, shrimp and the bacteria in a filter. Water conditioners are made for this range.
Published by your utility: City of Oxnard Water Division's 2024 water quality report.
Water chemistry
General hardness
135–551 ppm
Typical 518 ppm
Hard. Ideal for livebearers and African cichlids. Soft-water species may struggle to breed.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
Carbonate hardness (alkalinity)
160–200 ppm
Typical 200 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
pH
7.6–7.7
Typical 7.7
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
Total dissolved solids
270–1200 ppm
Typical 960 ppm
A rough measure of everything dissolved in the water. RO water reads near 0, so TDS is a quick way to compare waters.
From California Water Board lab results; City of Oxnard Water Division's 2024 water quality report (2023–2026).
- City of Oxnard Water Division adds phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Oxnard, CA
United Wtr Cons Dist
Serves 50% of residents · Groundwater fed by surface water · Chloramine
- 2024 water quality report
City of Oxnard Water Division
Serves 49% of residents · Buys water from Calleguas Municipal Water Dist · Chloramine
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.