Escondido, CA tap water
Supplied mostly by City of Escondido, 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 1 ppm (Low)
Typically not detected
Not detected in testing, so water changes lower your tank's nitrate well.
From California Water Board lab results; San Diego County Water Authority, which supplies Rincon del Diablo MWD (Id-1) (2023–2026).
Copper at home taps
0.15–0.22 ppm (Worth knowing)
Typical 0.22 ppm
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.
From California Water Board lab results (2024–2025).
Water chemistry
General hardness
209–210 ppm
Typical 210 ppm
Moderately hard. Great for livebearers, and most community fish adapt.
From California Water Board lab results; San Diego County Water Authority, which supplies Rincon del Diablo MWD (Id-1) (2023–2026).
Carbonate hardness (alkalinity)
115–119 ppm
Typical 115 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results; San Diego County Water Authority, which supplies Rincon del Diablo MWD (Id-1) (2023–2026).
pH
7.9–8
Typical 8
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results; San Diego County Water Authority, which supplies Rincon del Diablo MWD (Id-1) (2023–2026).
Total dissolved solids
485–520 ppm
Typical 485 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; San Diego County Water Authority, which supplies Rincon del Diablo MWD (Id-1) (2023–2026).
- City of Escondido adds phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Escondido, CA
City of Escondido
Serves 81% of residents · Lake or river water · Chloramine
Rincon del Diablo MWD (Id-1)
Serves 14% of residents · Buys water from San Diego County Water Authority · 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.