Stockton, CA tap water
Supplied mostly by California Water Service (Cal Water) - Stockton District, plus 1 other utility. Here's what the water means for your fish.
Disinfectant
Chlorine
Your water is treated with chlorine. It slowly gases off from standing water, and any water conditioner removes it.
Safety for fish and shrimp
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)
Up to 38 ppm (Low)
Typical 9.7 ppm
Water changes can't take your tank's nitrate below this level.
From California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Board lab results (2023–2026).
Copper at home taps
Up to 0.01 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 (2023–2024).
Chlorine or chloramine at the tap
0.1–1.8 ppm
Typical 0.9 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: California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Service - Stockton District's 2024 water quality report.
Water chemistry
General hardness
23–290 ppm
Typical 27 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
Published by your utility: California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Service - Stockton District's 2024 water quality report.
Carbonate hardness (alkalinity)
30–270 ppm
Typical 30 ppm
Little buffering. pH can drop quickly between water changes, especially with CO₂ or an older tank.
Published by your utility: California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Service - Stockton District's 2024 water quality report.
pH
5.8–8.9
Typical 8
Most community fish do well here. Stable water matters more than the exact number.
Published by your utility: California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Service - Stockton District's 2024 water quality report.
Total dissolved solids
40–460 ppm
Typical 40 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: California Water Service (Cal Water) - Stockton District's 2024 water quality report; California Water Service - Stockton District's 2024 water quality report.
Who supplies Stockton, CA
- 2024 water quality report
California Water Service (Cal Water) - Stockton District
Serves 58% of residents · Lake or river water · Chlorine
- 2024 water quality report
California Water Service - Stockton District
Serves 41% of residents · Buys water from Stockton East Water District · Chlorine
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.
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Compiled by Shoal & Stem from public records. Free to cite with a link.