Mountain House, CA tap water
Supplied by City of Mountain House. Here's what its 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)
0.9 ppm (Low)
Low, so water changes lower your tank's nitrate well.
From California Water Board lab results (2023–2026).
Copper at home taps
0.05 ppm (Low)
Low. Water that sits in household pipes overnight can carry more than this.
From California Water Board lab results (2023–2025).
Water chemistry
General hardness
73 ppm
Moderately soft to medium. Suits most community fish and plants.
From California Water Board lab results (2023–2026).
Carbonate hardness (alkalinity)
65 ppm
Moderate buffering. pH should stay fairly steady.
From California Water Board lab results (2023–2026).
pH
8
Alkaline. Many utilities raise pH to protect pipes. Stability matters more than the exact number.
From California Water Board lab results (2023–2026).
Total dissolved solids
185 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 (2023–2026).
Who supplies Mountain House, CA
City of Mountain House
Serves 91% of residents · Lake or river water · 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.
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Compiled by Shoal & Stem from public records. Free to cite with a link.