Rocklin, CA tap water
Supplied by Placer Cwa - Foothill. Here's what its 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 (2023–2025).
Nitrate (NO₃)
Not detected (Low)
Not detected in testing, so water changes lower your tank's nitrate well.
From California Water Board lab results (2023–2025).
Copper at home taps
Not detected (Low)
Not detected in testing. Water that sits in household pipes overnight can still pick some up.
From California Water Board lab results (2025).
Water chemistry
General hardness
18–19 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 (2023–2025).
Carbonate hardness (alkalinity)
20–21 ppm
Typical 21 ppm
Little buffering. pH can drop quickly between water changes, especially with CO₂ or an older tank.
From California Water Board lab results (2023–2025).
pH
7.1–8.9
Typical 8.3
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
38–82 ppm
Typical 60 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 (2023–2025).
Who supplies Rocklin, CA
Placer Cwa - Foothill
Serves 96% of residents · Lake or river water · 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.