How to Clean a Fish Tank / aquarium ? (Feb 2019)

How to Clean an Fish Tank

In the aquarium hobby cleaning a fish tank is a crucial part, which is very important to keep your pet healthy and happy in your aquarium.

Cleaning a Fish tank is easy its just removing all unwanted waste, Ammonia, Nitrite and unwanted matters from the Aquarium Water. This process will keep your fish Healthy, happy and will live a long life.

Cleaning a Fish Tank is easy if you follow step by step instruction mentioned below, if you miss out on some small details you will mess up the Cycled Fish tanks environment and it might be fatal for your aquarium pets.

Step 1: Keep all the necessary items handy.

  • Cotton cloth 2
  • Toothbrush
  • Fishnet
  • Fish container
  • Small Mug
  • Bucket of proper size to syphon the aquarium water
  • Dechlorinated water
  • Tap water Dechlorinator

Step 2: Take out all the decorations, filters etc from the tank.

Before you remove the decorations, filters from the aquarium make sure your hands are clean and free from any soap or chemicals. If accidentally you mix soap or chemicals into the aquarium water it might pollute the water and it will harm your pet.

The Aquarium should be free to access, keep only the stones or sand which is in the bottom untouched. This will make the next step easier.

Step 3: Remove the fish from the aquarium.

Remove top layer of water and fill it in Fish container once it’s filled up, use the fish net to remove you fish from your fish tank and safely move your fish into it. Fish will behave or act scared and move aggressively to make sure you cover the top of the container to be on the safer side as your fish might jump off the container.

Step 4: Remove the fish tank water

Use a mug and remove the water from the fish tank without disturbing the bottom layer, move the water to a clean bucket free from dust, chemicals, soap water etc. once you have moved at least 50% of the water of the tank or max you can take out of the tank which is clean.  Caution be careful with this water as you will be using the water again in the aquarium, avoid introducing any chemical or matter into this water.

Now shake the bottom layer to remove all the waste or food which has stuck or sunk over a period of time to the bottom. Remove all the dirty water and rinse off the stones or sand which you are using.

Step 5: Clean the tank

Now you can clean the decorative, air stone, stones etc.  free all the decorative from the algae or any dust or unwanted matters.

Wipe the glass with a cotton towel or paper towel, free it from algae or any build up you could see from the glass. Use the brush to remove the algae from the corners which are difficult to clean using the towel. If the aquarium is dry you can use tap water to wet your towel.

Don’t use any chemical or soapy water to clean any of the parts of your aquarium, decorative, air stone etc. If will pollute the water and can be fatal for your pet.

Step 6: Add water to your tank.

Take the stored water from the aquarium and pour it genteelly back into the aquarium. Now when you add additional water you can use tap water but before introducing the water you have to process the water. You have to use dechlorinator to process the tap water to remove the chlorine content from the water then add it to the tank.

Make sure to have enough space in the aquarium to fill the water in which the fishes are kept. Add Dechlorinator as you have used tap water to clean the aquarium.

Now Introduce the decoratives, air stone, filters etc into the aquarium. Turn on all the equipment’s in the aquarium and let the for Half an Hour to one Hour. This will cycle the tank and the temperature of the tank will come back to normal. If you use a heater switch it on to the temperature you usually maintain.

Step 7: Add your fish to the tank.

Be gentle while handling the container in which your fish is kept, to reduce the stress level. Please note it is stress full for a fish during the water change as the fish is moved from its home but it’s a absolute necessity to do it.

Now slowly move your fish into the clean water in the aquarium which your fish will love.


Partial water Change:

It is a good habit to have a partial water change in your aquarium every week or 2 week once. To do a partial water change you would require basic materials as mentioned below.

  • Siphoning Vacuum pump
  • Bucket
  • Dechlorinator
  • Magnetic Cleaner

It is recommended to do a partial water change of at least 20 to 30% of water in the aquarium weekly once or once in two week.

 Step 1:

Clean the glass using Magnetic Cleaner to remove any algae build up. Use it on all sides of the glass and remove the algae completely. Be careful not to stress the fish in the process.

Step 2:

Use the Siphoning Vacuum Pump to remove the water safely out of the water without disturbing the fishes of plants. You can vacuum the debris stuck in between the stones or decorative which will reduce the Ammonium build up.

This will remove most of the harmful Ammonium and Nitrites build up over a period of time and rest of them will be taken care of by your filters.

Step 3:

This step is to introduce the water to the aquarium, this is an important process as you have to process the water before introducing it to the aquarium.

If you are using the tap water use a dechlorinator to remove the chlorine present in water. If the temperature of the water is too cold use your aquarium heater and get the temperature to aquarium water temperature. When adding the water be gentle and add it slowly without the disturbing the fish or decorative etc.

Step 4:

Observe the aquarium and if you find too much of algae build up you have to control it instantly or it will take over your aquarium in no time. Add Algae Control liquid to remove the algae or keep it under control.


How frequently should you change the water?

This depends on the below factors in the aquarium

  • Size of the tank
  • Number of fish you have in the aquarium
  • How much you feed the fish
  • Filtration system used
  • Many more

To understand the basics of how the fish tank gets dirty I have a small explanation below.

Nitrogen Cycle in an aquarium


As the info graphic shown above the leftover food and the Poop of the fish pollutes the water and gets converted to Ammonia and Nitrosomonas bacteria converts it into Nitrite.

Both Ammonia and Nitrite is harmful for fish it’s the main reason why the fish gets sick and sometimes die if the build up is too much.

Good news is there are another set of bacteria which will convert the Ammonia and Nitrite to Nitrate which is not harmful to the fish. It depends on what kind of filters you are using and the conducive atmosphere for the bacteria to convert the harmful chemicals to Nitrate.

Base line is it depends on how much food and fish you have and how much waste they produce and it depends on the size of aquarium, smaller the aquarium you need to do a frequent water change. If you have good filters they are a relief as they build up the good bacteria and control Ammonia and Nitrite build up.

Bottom line is its always better to do partial water change atleast weekly once or once in 2 week.

Don’t do complete water change frequently as it is stress full for the fish and it will take time for your aquarium to come to perform better in breaking the Ammonia and Nitrite.



Keeping a fish is a reward full hobby it is a wonderful experience to keep a beautiful aquarium. But it’s our responsibility to keep it clean and in a good condition to enjoy the benefits of the aquarium.

Cleaning the fish tank is not a heard task its easy if you follow the steps given and keep all the things handy. There is an advantage of cleaning an aquarium, if improves your patience and concentration as you need your full attention while doing the water change in an aquarium.

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