Oak View, CA tap water
Supplied mostly by Casitas Municipal Water Dist, plus 1 other utility. 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)
0.9–15 ppm (Low)
Typical 2.2 ppm
Low, so water changes lower your tank's nitrate well.
From California Water Board lab results; EPA monitoring data (2014–2026).
Copper at home taps
0.09–0.37 ppm (Worth knowing)
Typical 0.37 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 (2023–2025).
Water chemistry
General hardness
278–284 ppm
Typical 281 ppm
Hard. Ideal for livebearers and African cichlids. Soft-water species may struggle to breed.
From California Water Board lab results; Casitas Municipal Water Dist, which supplies Ventura River Water District (2023–2026).
Carbonate hardness (alkalinity)
150 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results; Casitas Municipal Water Dist, which supplies Ventura River Water District (2023).
pH
7.4–7.5
Typical 7.5
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results; Casitas Municipal Water Dist, which supplies Ventura River Water District (2023).
Total dissolved solids
415 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; Casitas Municipal Water Dist, which supplies Ventura River Water District (2023–2026).
Who supplies Oak View, CA
Casitas Municipal Water Dist
Serves 75% of residents · Lake or river water · Chlorine
Ventura River Water District
Serves 26% of residents · Buys water from Casitas Municipal Water Dist · 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.
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Compiled by Shoal & Stem from public records. Free to cite with a link.