Tustin, CA tap water
Supplied mostly by Irvine Ranch Water District, plus 1 other utility. Here's what the water means for your fish.
Disinfectant
Chloramine
Your water is treated with chloramine. Unlike chlorine, it doesn't gas off when water sits out, and many pitcher and fridge filters aren't rated to remove it. Conditioners that list chloramine on the label break it apart, which frees about 0.44 ppm of ammonia here. Some utilities switch to plain chlorine for a few weeks a year.
Safety for fish and shrimp
Ammonia (with conditioner)
Estimate0.27–1.31 ppm (Low)
Typical 0.44 ppm
This is what a conditioner frees when it breaks the chloramine apart. A cycled filter clears it within a day.
Estimated from the chloramine level Irvine Ranch Water District reports (2025).
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)
Up to 19 ppm (Low)
Typical 1.2 ppm
Low, so water changes lower your tank's nitrate well.
From California Water Board lab results (2023–2026).
Copper at home taps (first draw)
0.08–0.25 ppm (Worth knowing)
The 90th percentile of first-draw samples from homes: water that sat in household pipes for at least six hours.
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 Irvine Ranch Water District's 2025 water quality report; California Water Board lab results (2024–2025).
Chlorine or chloramine at the tap
1.1–5.4 ppm
Typical 1.8 ppm
At tap levels, chlorine and chloramine are toxic to fish, shrimp and the bacteria in a filter. Water conditioners are made for this range.
Published by your utility: Irvine Ranch Water District's 2025 water quality report.
Water chemistry
General hardness
52–469 ppm
Typical 236 ppm
Hard. Ideal for livebearers and African cichlids. Soft-water species may struggle to breed.
From Irvine Ranch Water District's 2025 water quality report; California Water Board lab results.
Carbonate hardness (alkalinity)
65–269 ppm
Typical 119 ppm
Strong buffering. pH stays steady and hard to lower without RO water.
From Irvine Ranch Water District's 2025 water quality report; California Water Board lab results (2025–2026).
pH
7–8.6
Typical 7.8
Most community fish do well here. Stable water matters more than the exact number.
From Irvine Ranch Water District's 2025 water quality report; California Water Board lab results (2023–2025).
Total dissolved solids
196–873 ppm
Typical 507 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 Irvine Ranch Water District's 2025 water quality report; California Water Board lab results (2023–2026).
Who supplies Tustin, CA
- 2025 water quality report
Irvine Ranch Water District
Serves 37% of residents · Lake or river water · Chloramine
City of Tustin
Serves 36% of residents · Buys water from East Orange County WD - Wz · Chloramine
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.