Poplar-Cotton Center, CA tap water
Supplied mostly by Poplar Comm Service 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
Nitrate (NO₃)
19–21 ppm (Worth knowing)
Typical 20 ppm
High for tap water. Water changes can't take your tank's nitrate below this level.
From California Water Board lab results, measured before treatment (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 (2023–2025).
Water chemistry
General hardness
130–170 ppm
Typical 150 ppm
Moderately hard. Great for livebearers, and most community fish adapt.
From California Water Board lab results, measured before treatment (2025).
Carbonate hardness (alkalinity)
97–160 ppm
Typical 129 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From California Water Board lab results, measured before treatment (2025).
pH
7.5–7.9
Typical 7.7
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results, measured before treatment (2025).
Total dissolved solids
230–310 ppm
Typical 275 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 (2025).
Who supplies Poplar-Cotton Center, CA
Poplar Comm Service Dist
Serves 99% of residents · Groundwater (wells) · Chlorine
Williams Mutual Water Company
Serves 10% of residents · Groundwater (wells) · Disinfectant not listed
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.