Manassas, VA tap water
Supplied mostly by City of Manassas, plus 2 other utilities. 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 0.75 ppm of ammonia here. Some utilities switch to plain chlorine for a few weeks a year.
Safety for fish and shrimp
Ammonia (with conditioner)
Estimate0.15–1.02 ppm (Worth knowing)
Typical 0.75 ppm
This is what a conditioner frees when it breaks the chloramine apart. A cycled filter clears it within a day; a big water change in a new or very small tank adds more of it at once. Some conditioners also bind ammonia for a day or so.
Estimated from the chloramine level Prince William Water reports (2024).
Nitrite (NO₂)
Up to 0.53 ppm (Low)
Typically not detected
Not detected in testing, so any nitrite in your tank comes from the tank itself.
From EPA monitoring data; Prince William Water's 2024 water quality report (2014–2024).
Nitrate (NO₃)
Up to 6 ppm (Low)
Typically not detected
Not detected in testing, so water changes lower your tank's nitrate well.
From EPA monitoring data; Pwcsa - West and City of Manassas, which supplies City of Manassas Park; Prince William Water's 2024 water quality report (2014–2024).
Copper at home taps (first draw)
0.18 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.
Published by your utility: Prince William Water's 2024 water quality report.
Chlorine or chloramine at the tap
0.6–4.2 ppm
Typical 3.1 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: Prince William Water's 2024 water quality report.
Water chemistry
General hardness
Supplier's figure84–170 ppm
Typical 127 ppm
Moderately soft to medium. Suits most community fish and plants.
From the utility that supplies yours: Fairfax County Water Authority, which supplies City of Manassas Park; Fairfax County Water Authority, which supplies Prince William Water.
Carbonate hardness (alkalinity)
39–88 ppm
Typical 39 ppm
Moderate buffering. pH should stay fairly steady.
From EPA monitoring data; City of Manassas, which supplies City of Manassas Park; City of Manassas and Fairfax County Water Authority, which supplies Prince William Water (2012–2019).
pH
7.3–7.6
Typical 7.6
Most community fish do well here. Stable water matters more than the exact number.
From EPA monitoring data; City of Manassas, which supplies City of Manassas Park; City of Manassas and Fairfax County Water Authority, which supplies Prince William Water (2012–2019).
- City of Manassas, City of Manassas Park and Prince William Water add phosphate to protect pipes. It can feed algae in tanks without much plant growth.
Who supplies Manassas, VA
City of Manassas
Serves 73% of residents · Lake or river water · Chloramine
City of Manassas Park
Serves 21% of residents · Buys water from Pwcsa - West · Chloramine
- 2024 water quality report
Prince William Water
Serves 5% of residents · Buys water from City of Manassas · 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.