Shoal & Stem
Tap water lookup

Mankato, MN tap water

Supplied by Mankato. Here's what its 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)

Area estimate

0.5–68 ppm (Worth knowing)

Typical 11 ppm

Water changes can't take your tank's nitrate below this level.

Area estimate from nearby wells: USGS well samples in your state (2000–2018).

Chlorine or chloramine at the tap

1.1–1.7 ppm

Typical 1.2 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.

From EPA monitoring data (2017–2019).

Water chemistry

General hardness

Not published yet

We haven't found this number yet. A drop test kit gives you your exact reading.

Carbonate hardness (alkalinity)

290–300 ppm

Typical 295 ppm

Strong buffering. pH stays steady and hard to lower without RO water.

From EPA monitoring data (2012–2019).

pH

Not published yet

We haven't found this number yet. A drop test kit gives you your exact reading.

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

Who supplies Mankato, MN

  • Mankato

    Serves 92% of residents · Groundwater fed by surface water · 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.

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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