What Are Ideal Water Conditions For Neon Tetras? {Do I Need a Testing Kit?}

Neon tetras are tropical freshwater fish, but can we replicate their water conditions in our aquarium?

Are you worried that if the water parameters are not right, your neon tetras may suffer?

In this article, we’ll make sure to highlight the ideal water conditions for neon tetras.

What Are Ideal Water Conditions For Neon Tetras?

Neon tetras need specific water requirements starting with a temperatures set at 72°-76°F or 22.2°-24.4°C. Ammonia and Nitrites need to be a 0 ppm. The PH balance must be between 6.0-7.0.

Using a water testing kit weekly and frequent water changes at 25-50% would be wise when keeping neon tetras.

What Are The Water Conditions For Neon Tetras In The Wild?

Neon tetras derive from South American tropical temperatures in and around the Amazon basin. The water itself is warm and acidic. There are plenty of plants in their surrounding habitat.

The freshwater is clear enough to be free of mud. Neon tetras would not thrive in water that is muddy. They are native to blackwater and clearwater streams. Neon tetras prefer moderate to mild currents and they prefer to swim in basins.

What Are The Exact Water Parameters For Neon Tetras in An Aquarium?

Attempting to replicate the natural conditions that neon tetras come from is the challenge. It’s clearly possible and exact parameters are highlighted below. The minimum or maximum amounts for each category can be debated slightly.

  • Temperature: 72°-76°F (22.2°-24.4°C)
  • Nitrite: 0 ppm
  • Ammonia: 0 pp
  • Nitrate: <20 ppm
  • PH: 6.0-7.0
  • General Hardness (GH): <10 dGH (<166.7 ppm)
  • Carbonate Hardness (KH): 1-2 dKH (17.8- 35.8ppm)
  • Alkalinity: 1- 2 dKH or 17.8 to 35.5 ppm

What Is The Best Temperature For Neon Tetras?

The temperature of your tank is crucial to the survival of your neon tetras. They do not like sudden changes in temperature. A water heater should be necessary in conditions that rise above or below 72°-76°F.

Changes in season and outdoor temperature will affect the warmth of the water in your aquarium. Many fish will be able to forgive these temperature fluctuations, but neon tetras are more sensitive to this.

Their natural habitat is always warm and we’re trying to mimic this to keep neon tetras comfortable and healthy. The actual limit of how high the temperature can be without stressing the neon tetras can be as much as 81°F. Lower than 72°F will be a problem.

Is Nitrite Tolerable For Neon Tetras?

Neon tetras are small and this makes them more susceptible to changes in the water quality. Nitrates are compounds that are unstable and unfriendly for all neon tetras.

They cannot live in a tank with any nitrates. It must be kept to 0 to protect the health of neon tetras. Nitrite can be converted to nitrate which is more tolerable. Nitrite is toxic while nitrate is not for neon tetras.

Can Neon Tetras Handle Ammonia In Their Tank?

Fish produce ammonia from their waste and debris from their leftover food. Ammonia is also toxic to neon tetras. Please try to keep this level at 0 as well. They cannot tolerate it.

Ammonia damages the gills on neon tetras. Breathing will eventually become strained and difficult. It will result in their eventual death.

Thankfully the bacteria that runs through a tank converts and feeds off ammonia that plants also enjoy and thrive on. A correctly cycled tank will help to manage ammonia levels. Plants also assist to lower these levels and keep them at 0 ppm.

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How Much Nitrate Is Ok For Neon Tetras?

Nitrate is more tolerable for neon tetras. 20 ppm (parts per million) is considered to be the maximum and keeping it less than this figure would be best. If the levels rise above 20 ppm, you will notice signs of stress in your neon tetras.

When ammonia is converted in your tank, nitrates are produced. Bacteria and nitrate levels help to balance out a cycled tank to keep conditions ideal.

What Is The Correct pH Level For Neon Tetras?

The ideal water for neon tetras is water that is more acidic. It is also soft water that mimics their natural habitat. 6.0-7.0 is ideal, but going as low as 5.5 will be tolerable.

If you want ideal breeding water, then a pH balance higher than 6.5 is not recommended. The neon tetras don’t reproduce well under higher levels.

Changes in acidity will create issues that will be obvious to the careful observer. You neon tetras will show signs of stress.

What Are The Best General Hardness, KH and Alkalinity Levels For Neon Tetras?

Carbonate or bicarbonates will be present in the water. Keeping them under control will keep your neon tetras healthy. General hardness levels should be fewer than 10 dGH or 166.7 ppm. General hardness keeps magnesium and calcium levels in check.

KH or Carbonate hardness should be at 1-2 dKH or between 17.8-35.8 ppm. Alkalinity measures the presence of carbonates and bicarbonates. The levels for Alkalinity and KH are the same.

What Will Happen To Neon Tetras If Water Parameters Are Incorrect?

We face the challenge of keeping neon tetras alive and well in our aquariums. If there are sudden changes to water parameters, the result will be illness or death. If the parameters are adjusted before any major changes, we can prevent the degree of harm caused to neon tetras.

You will notice signs that indicate stress:

  • Twitching
  • Loss of color
  • Erratic or chaotic swimming
  • Sluggish or weakened swimming
  • Loss of appetite
  • Excessive hiding

There are more indicators, but it’s best to avoid them by using a water testing kit weekly.


Test your water parameters to keep them ideal for neon tetras. Add plants to clean the tank and bring in more oxygen. A heater works best to maintain the warmer temperature neon tetras are used to. Use a filter to help with aeration. Water softeners also work well if the water is too hard.

Neon tetras are sensitive to the changes in the water. Do things gradually and you will avoid causing chaos or stress for neon tetras.

Brian Arial

Brian Arial has kept fish for leisure and worked with fish stores for most of his life. He enjoys writing and caring for aquariums and ponds.