Shoal & Stem
Tap water lookup

Norman, OK tap water

Supplied by Norman Utilities Authority. Here's what its 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 0.49 ppm of ammonia here. Some utilities switch to plain chlorine for a few weeks a year.

Safety for fish and shrimp

Ammonia (with conditioner)

Estimate

0.49–0.73 ppm (Low)

Typical 0.49 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 Norman Utilities Authority reports (2025).

Nitrite (NO₂)

Up to 0.05 ppm (Low)

Typically not detected

Not detected in testing, so any nitrite in your tank comes from the tank itself.

From EPA monitoring data (2012–2019).

Nitrate (NO₃)

1–2.7 ppm (Low)

Typical 1.8 ppm

Low, so water changes lower your tank's nitrate well.

From EPA monitoring data (2012–2017).

Chlorine or chloramine at the tap

2–3 ppm

Typical 2 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: Norman Utilities Authority's 2025 water quality report.

Water chemistry

General hardness

75 ppm

Moderately soft to medium. Suits most community fish and plants.

Published by your utility: Norman Utilities Authority's website.

Carbonate hardness (alkalinity)

10–247 ppm

Typical 41 ppm

Moderate buffering. pH should stay fairly steady.

Published by your utility: Norman Utilities Authority's 2025 water quality report.

pH

8.9

Alkaline. Many utilities raise pH to protect pipes. Stability matters more than the exact number.

Published by your utility: Norman Utilities Authority's website.

  • Norman Utilities Authority adds phosphate to protect pipes. It can feed algae in tanks without much plant growth.
  • Norman Utilities Authority softens its water at the plant, so it may be softer than the local groundwater.

Who supplies Norman, OK

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.

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