Folsom, CA tap water
Supplied mostly by Folsom, City of - Main, plus 3 other utilities. 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)
Not detected (Low)
Not detected in testing, so water changes lower your tank's nitrate well.
From California Water Board lab results; California Water Board lab results, measured before treatment (2023–2026).
Copper at home taps
Up to 0.14 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).
Water chemistry
General hardness
17–29 ppm
Typical 18 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
From California Water Board lab results; California Water Board lab results, measured before treatment (2023–2026).
Carbonate hardness (alkalinity)
14–26 ppm
Typical 22 ppm
Little buffering. pH can drop quickly between water changes, especially with CO₂ or an older tank.
From California Water Board lab results; California Water Board lab results, measured before treatment (2023–2026).
pH
6.7–7.8
Typical 7.7
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results; California Water Board lab results, measured before treatment (2023–2026).
Total dissolved solids
31–56 ppm
Typical 56 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; California Water Board lab results, measured before treatment (2023–2026).
Who supplies Folsom, CA
Folsom, City of - Main
Serves 76% of residents · Lake or river water · Chlorine
Folsom State Prison
Serves 7% of residents · Lake or river water · Disinfectant not listed
San Juan Water District
Serves 6% of residents · Lake or river water · Chlorine
Folsom, City of - Ashland
Serves 5% of residents · Buys water from San Juan 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.
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.