Rio Vista, CA tap water
Supplied by City of Rio Vista. 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
Nitrate (NO₃)
Up to 13 ppm (Worth knowing)
Typical 10 ppm
Water changes can't take your tank's nitrate below this level.
From California Water Board lab results, measured before treatment (2023–2026).
Water chemistry
General hardness
22–85 ppm
Typical 69 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
From California Water Board lab results, measured before treatment (2023–2026).
Carbonate hardness (alkalinity)
250–270 ppm
Typical 260 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results, measured before treatment (2023–2026).
pH
8.4
Alkaline. Many utilities raise pH to protect pipes. Stability matters more than the exact number.
From California Water Board lab results, measured before treatment (2024–2025).
Total dissolved solids
430–620 ppm
Typical 500 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, measured before treatment (2023–2026).
Who supplies Rio Vista, CA
City of Rio Vista
Serves 97% of residents · Groundwater (wells) · 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.