Dublin, CA tap water
Supplied mostly by Zone 7 Water Agency, 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 a little ammonia. Some utilities switch to plain chlorine for a few weeks a year.
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 18 ppm (Low)
Typical 2.5 ppm
Low, so water changes lower your tank's nitrate well.
From California Water Board lab results; Zone 7 Water Agency, which supplies Dublin San Ramon Services District (2023–2026).
Copper at home taps
Up to 0.13 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 (2023–2026).
Water chemistry
General hardness
79–368 ppm
Typical 146 ppm
Moderately hard. Great for livebearers, and most community fish adapt.
From California Water Board lab results; Zone 7 Water Agency, which supplies Dublin San Ramon Services District (2023–2026).
Carbonate hardness (alkalinity)
80–274 ppm
Typical 138 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results; Zone 7 Water Agency, which supplies Dublin San Ramon Services District (2023–2026).
pH
7.4–8.8
Typical 8
Alkaline. Many utilities raise pH to protect pipes. Stability matters more than the exact number.
From California Water Board lab results; Zone 7 Water Agency, which supplies Dublin San Ramon Services District (2023–2026).
Total dissolved solids
210–568 ppm
Typical 239 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; Zone 7 Water Agency, which supplies Dublin San Ramon Services District (2023–2026).
- Zone 7 Water Agency and Dublin San Ramon Services District soften their water at the plant, so it may be softer than the local groundwater.
Who supplies Dublin, CA
Zone 7 Water Agency
Serves 52% of residents · Lake or river water · Chloramine
Dublin San Ramon Services District
Serves 51% of residents · Buys water from Zone 7 Water Agency · 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.