How To Test Fish Tank Water Without A Kit

how to test your fish tank water without a kit

How To Test Fish Tank Water Without A Kit7 mins read

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How to test fish tank water without a kit
Image from Flickr

Wondering how to test fish tank water without kit?

Do you want to correctly know your tank’s water parameters? You’ll need the correct kit. However, there are times you may not be able to access one.

One of the most important parts of owning an aquarium is maintaining the correct water parameters. These should stay constant for the specific species of inhabitants in the aquarium.

A well-cycled aquarium should look clear, with healthy and vibrant fish. This kind of tank should not require regular parameter checks.

However, a new aquarium, younger than six months may need proper testing. This is also the case after doing any major cleaning. If you are wondering ‘how to test my fish tank water without a kit?’, read on.

However, note that the methods in this article are temporary. It’s best not to rely on them long-term. However, they can do when you need a quick solution. So, let’s look at the main methods of testing the different parameters in an average fish tank…

How To Test Aquarium Water Without A Kit

fish for a 3 gallon tank
Visible water conditions may similarly indicate a poor nitrogen cycle in your tank, in which case you can use bacteria alternatives or introduce more live plants and decor that contains natural bacteria. Image from

Ideally, every fish keeper must have an aquarium testing kit, and thermometer at hand.

Should you not have  a testing kit yet, there are a few other methods you can follow without a kit:

Methods To Test Your Fish Tank Water Without A Kit

1. Visual Testing

Usually, when aquarium water is in poor condition, there will be some visual indicators.

Water that looks cloudy, dirty, or even green indicates significant unfavorable water parameters. Mostly a good scrub-down will remove algae buildup. On top of this, a partial water change should clear up the water.

Visible water conditions may similarly indicate a poor nitrogen cycle in your tank. In this case, you can use bacteria alternatives. You can also introduce more live plants and decor that contain natural bacteria.

2. Fish Behaviour

You can easily test aquarium water without kit by observing the behavior of your fish.

However, bear in mind this is not a method you should actively use! In fact, when they start showing strange behavior it may already be too late. That said, here are some symptoms to look out for.

  • These are the most common behavioral traits in fish with poor tank water parameters;
  • Loss of Appetite.
  • Stress or depression, shying away.
  • Gasping for air at the surface of the tank.
  • Spend most of their time hiding, or at the bottom of the tank.
  • They have red or damaged gills.
  • There are white parasites on them.
  • They are swimming frantically around the tank.
  • Strange swimming patterns.
  • Fish seem weak and lethargic.
  • They are floating on the surface of the tank.
  • There is a sudden change of color in your fish or discolored patches are appearing.

The behaviors we mention here usually indicate poor water conditions. Many times it can point to Ammonia poisoning, which can lead to health issues and even death.

Remember, aquarium testing kits will be a much cheaper option than a vet visit or treating sick fish. It may be tempting to learn how to test your fish tank water without a kit. However, that doesn’t mean it’s advisable. In fact, it can lead to any of the above symptoms.

Thus at this stage, it would be wise to do a proper full-parameter test with a testing kit.

3. Pet Store Help

Ideally, if you need to do an emergency test without a kit you could always ask for help from a local pet store.

Local stores may be able to do a quick test on a sample of aquarium water, for a price usually, or if you are lucky for free.

4. Test Strips

In some circumstances, an aquarium testing kit may be out of your budget range for the time being.

In this case, there is always the option of testing strips. Testing strips are more affordable than full test kits and will give accurate results, fast. Similarly, they are disposable and less of a hassle than a full testing kit.

How To Test Specific Parameters

How to test specific parameters
You can check for condensation to see how cold water is. Water in a Glass or metal container that leads to condensation on the outside means that the water inside the container is colder than the room temperature. Image from Flickr

1. Ammonia

Want the most accurate way to check for excessive ammonia in your tank? For this parameter, to test fish tank water without kit, you should observe your fish. If they have a loss of appetite, are lethargic, stressed, and tend to sink to the bottom of the tank, your ammonia levels are too high!

In this case, a proper water change is vital. You should also take steps to improve nitrogen cycling.

Unlike pH, there aren’t any ‘home tests’ you can do. On top of this, ammonia poisoning can kill quickly, so it’s not advisable to try.

The best way however to test for Ammonia is to use a proper API ammonia testing kit, available at most pet stores.

2. pH

Did you know you can test tank pH without a kit? However, this method takes a long time, and isn’t always correct. For the test, you will need a red cabbage and a glass bowl. Then, follow the instructions below:

  • Grate some of the cabbage and boil two cups or 470ml of distilled water.
  • Place the grated cabbage in the glass bowl and pour the boiling water over it.
  • After 30 minutes strain the water and you will have a testing solution.
  • You can pour a few drops of cabbage juice into a sample of aquarium water.
  • If that water turns pink it is more acidic, if the water is a deep violet color the pH is around 6.0.
  • A bluish color indicates that the water pH is around 7.0
  •  green indicates a pH of between 11 and 12.

3. Temperature

At some stage, you will need to check your tank’s temperature. If you do not have a waterproof thermometer on hand, there are alternatives. These other methods won’t give an exact answer, but they can show you roughly where the levels are.

  • Using hand or Elbow

For a rough idea hold your hand above the water, if you feel the heat radiating it is too hot and will burn, if you feel no heat, it will either be room temperature or cold. You can dip your elbow into the water to tell if it is hot or cold. Holding your elbow in the water for 5 – 10 minutes it should feel slightly warm indicating a temperature of around 100 °F (38 °C), and cooler for lower temperatures.

  • Bubble Test

When heating water in a pan or pot, small bubbles will start to form at the bottom.

This indicates the temperatures are roughly around 160 °F (71 °C). On top of this medium-sized bubbles indicate a higher temperature of around 175 °F (79 °C), Continuous chains of bubbles will form and start rolling when the water is at boiling point, around 212 °F (100 °C).

  • Testing Cold Water

You can check for condensation to see how cold the water is. Is the water in a glass or metal container?

This often leads to condensation on the outside. These water droplets mean that the water inside the container is colder than the room temperature.

Condensation will form faster as the water becomes colder. In most cases, water that is cold enough to cause condensation will be too cold for tropical or even cold-water freshwater fish.

In summary

So, you now have some options to get you by without a kit. However, this should only be when strictly necessary. Ideally, proper aquarium maintenance requires you to check conditions precisely.

Therefore, read on to see how you can improve conditions in your tank. This way, you won’t have as many issues with fish health, and you won’t have to test parameters as much anyway…

The Importance Of Proper Water Parameters In Your Fish Tank

Before getting to the question “how do I test my fish tank water without a kit?”,  you need to know why water parameters are so important.

in fact, the health of your aquarium inhabitants depends on maintaining proper water parameters. Routine testing is the only accurate way to ensure certain water parameters are within an acceptable range.

Basic Water Parameters

Basic water parameters
Though not entirely part of testing water parameters, for tropical fish, tropical water temperatures are required. Image from Flickr

There are a few water parameters which you will mostly need to test for:

1. Temperature

Though not entirely part of testing water parameters, tropical fish need tropical water temperatures!

Some freshwater tropical fish need very consistent temperatures to flourish. Unfortunately, the best way to ensure that water temperatures are consistent is to use a thermometer and heater. Most internal heaters, luckily, have a built-in thermometer.

Generally, most freshwater fish species will flourish in temperatures between 22 – 28°C or 72 – 82°F. Some species require higher, but other species such as Goldfish and Guppies enjoy cooler water temperatures. The most important factor is to always keep temperatures as stable as possible for tropical fish especially.

2. pH

Water pH is the measurement of how alkaline or acidic your tank water is. Specific aquarium inhabitants require specific pH ranges. Some species prefer slightly more acidic water, while others prefer high alkalinity.

A pH of between 6.0 and 7.0 will be more acidic, whereas higher than 7.0 will be more alkaline. Though for most tropical freshwater fish species pH levels between 6.5 and 7.5 are usually alright. Once again in terms of pH levels, stability is the key element. Rapid changes in pH can be fatal for some fish species.

  • How to Lower pH – A natural method to lower pH levels in your tank is to add peat moss to the filter, or to add Catappa leaves to your aquarium. Other than that, it can be done with chemicals.
  • How to Raise pH Levels – To raise pH levels and make water more alkaline, some baking soda can be added to your tank. One teaspoon per 5 gallons will create a small and safe increment. Similarly, never increase the pH levels rapidly.

3. Ammonia

Ammonia is an extremely toxic substance that comes from the decomposition of fish waste, leftover foods, and other organic substances. A tiny amount of Ammonia in your tank can destabilize the biological balance of an entire aquarium.

Ammonia spikes in your tank will generally lead to illness and even death of tropical fish species. Thus, it is crucial to always measure Ammonia levels properly. You should never be able to detect ammonia and nitrites in your aquarium after it has cycled completely. With that note, an important factor in any aquarium is what is called the Nitrogen Cycle.

Nitrogen Cycle. Image from Wikipedia.

Nitrogen Cycle is a common term in aquaria. It’s also an important factor in keeping proper water parameters. When micro organisms eat ammonia, they turn it into less toxic nitrites. Other things that help with this are beneficial bacteria from plants, substrate, filter media, driftwood, and other tank items.

The beneficial bacteria similarly feed off the nitrites and produce nitrates which are the least harmful.

Cycling your aquarium means there is enough biological filtration such as beneficial bacteria to eat all Ammonia and Nitrites. Removing and replacing water in your tank weekly will similarly help to keep nitrite and ammonia levels down. Ideally, your tank should have 0 ppm ammonia, and 0 ppm nitrites.

4. Carbonate Hardness / Alkalinity (KH)

Carbonate hardness in water refers to the measure of dissolved carbonates and bicarbonates in your tank water. The Carbonate hardness of your aquarium water helps to maintain a stable pH and buffers acidity. A degree of Carbonate Hardness (dKH) above 4 or 17.9 ppm is advisable to prevent pH levels from crashing. Beneficial bacteria in your tank naturally consume Carbonates, though the substrate will help to generate more.

5. General Hardness (GH)

General Hardness (GH) mainly refers to calcium and magnesium along with other metal ions detectable in the tank water. Because these compounds are so poorly soluble, they may cause lime deposits in the tank. A dGH of between 4 and 12 is suitable for tropical fish tanks, depending on the fish species that you are keeping. In cases where you have soft water in your tap, the GH is low, whereas harder water has a high GH.

6. Oxygen

Aquarium plants and fish require proper levels of oxygen to thrive and prevent susceptibility to disease. A proper filter along with live plants, and regular water changes will help to maintain oxygen levels.

7. Salinity

Salinity refers to the amount of salt dissolved in your aquarium. Most tropical aquariums require a certain amount of aquarium salts. Freshwater fish generally require a much lower salinity than marine fish. However, there are freshwater fish species, such as Guppies that prefer slightly higher salinity in their water.

Though water hardness, oxygen, and salinity are mentioned as basics, most testing kits, and natural testing methods mainly aim at testing pH and ammonia levels.

Proper Fish Tank Set-Up And Maintenance

Proper fish tank set-up and maintenance
As a result, proper aquarium set-up, a thorough nitrogen cycle, and regular cleaning and maintenance form an integral part of keeping your aquarium clean, and fish healthy and thriving.

As a result, proper aquarium set-up is crucial. A thorough nitrogen cycle, and regular cleaning and maintenance form an integral part of keeping your fish healthy and thriving. A few good housekeeping tips for your aquarium include:

Weekly water changes. This includes replacing between 25 – 30% of your tank water, siphoning it from the bottom, and adding new treated and heated water with the right parameters.

  • Remove any dead fish or plants immediately.
  • Changing water should it become cloudy.
  • Do not overfeed fish, and remove uneaten food.
  • Do not overcrowd your aquarium and stick to the correct ratios for the tank size.
  • Only fill your aquarium ¾ of its capacity and not full.
  • Do not just use one type of food over and over.
  • Use an aquarium lid, or cover.
  • Only change water if it shows discoloration or the fish show signs of distress, and unhealthy behaviour.
  • Invest in a proper filtration system.

Ideally, eventually, you will need to purchase a proper testing kit.

Final Thoughts

As can be noted from the gathered information, there are a few methods to test water parameters even water temperatures without a testing kit or thermometer. However, not all of them are accurate and reliable, and you will only be able to gather rough data or assumptions from most. Thus, it is crucial to have a proper testing kit and thermometer to keep your fish healthy and content, and to keep optimal water parameters.

Frequently Asked Questions

How Can I Keep Safe Water Parameters Without a Kit?
By following the “Housekeeping” methods in the Maintenance section, you can essentially keep safe water parameters without a testing kit. Ensuring that your tank is initially properly cycled, doing regular water changes, feeding a proper diet, and investing in a proper filter can keep the water clean and healthy.
How to Test Ammonia Levels Without a Test Kit?
You should be able to easily notice ammonia spikes in your tank when fish become stressed, lethargic, and show physical signs of damage such as red gills. Tired, and bottom swimming fish are similarly a clear indication of ammonia buildup.
How Can I Reduce Ammonia Levels Naturally?
The best method to reduce ammonia levels in your tank as fast as possible is to do a water change and filter and cycle your water with beneficial bacteria. Try not to overfeed your fish, and remove all waste as fast as possible to prevent ammonia spikes.
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