Lake Arrowhead, CA tap water
Supplied mostly by Lake Arrowhead CSD, plus 2 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; EPA monitoring data (2013–2026).
Copper at home taps
Up to 0.31 ppm (Worth knowing)
Typical 0.16 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 (2023–2024).
Water chemistry
General hardness
62–195 ppm
Typical 65 ppm
Soft. Good for tetras, rasboras and most shrimp. Livebearers, snails and African cichlids prefer harder water.
From California Water Board lab results; Clawa, which supplies Alpine Water Users Association (2023–2026).
Carbonate hardness (alkalinity)
62–190 ppm
Typical 64 ppm
Moderate buffering. pH should stay fairly steady.
From California Water Board lab results; Clawa, which supplies Alpine Water Users Association (2023–2026).
pH
7.4–8.3
Typical 7.5
Most community fish do well here. Stable water matters more than the exact number.
From California Water Board lab results; Clawa, which supplies Alpine Water Users Association (2023–2026).
Total dissolved solids
110–250 ppm
Typical 150 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; Clawa, which supplies Alpine Water Users Association (2023–2026).
- Lake Arrowhead CSD adds phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Lake Arrowhead, CA
Lake Arrowhead CSD
Serves 67% of residents · Lake or river water · Chlorine
Clawa
Serves 30% of residents · Lake or river water · Chlorine
Alpine Water Users Association
Serves 7% of residents · Buys water from Clawa · 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.