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How to Clean a Fish Tank with Fish in it

how to clean a fish tank with fish in it

Cleaning the fish tank is an essential factor in the aquarium’s overall maintenance procedure. Doing it the right way will help maintain a healthy environment and ecosystem inside the fish tank. However, cleaning the tank is not as simple as everybody thinks of because you will need to take some precautionary measures not to stress or disturbing the fish and its environment. But how to clean a fish tank with fish in it?

There are different ways to clean a fish tank, including removing the fish outside the aquarium. But doing this method can immediately affect the fish once you remove them from their habitat. In this article, we will be dealing with the proper way to effectively clean the fish tank without removing the fish in it.


Clean Fish Tank Without Removing the Fish

Cleaning the fish tank does not need to remove all the fish. I am talking about maintenance where cleaning is done on a regular basis, such as weekly, bi-weekly, or every two weeks, depending on your schedule. The key is you should never shock the entire ecosystem inside the fish tank. So, if you remove the fish, it means you are shocking the system. We can leave the fish inside the tank but still do our regular cleaning procedure.

Depending on your schedule, you will need to change 15 to 20 percent of the water, gravel cleans the sand, and clean the filter. But please remember to break up the cleaning process or not do it at the same time. For example, you can change the filter in one week, and you are doing the water change in another week, and so on. Doing this method will minimize the stress of the fish when doing all of these maintenance processes.

In addition, all of these practices require that you leave the fish in the tank. You don’t need to take the fish out. Probably, you will only need to take the fish out if you did a bad job in the maintenance or cleaning process where the aquarium already got the bloom of algae and other debris inside the tank. If you feel that you need a restart and need to clean everything because the aquarium is too dirty, then take the fish out and do your cleaning process.

Doing Regular Water Changes

Doing regular water changes plays a big role in fish keeping. Changing 10 to 15 percent of the water weekly can help in removing dirt, including ammonia and nitrates. But, if you feel that changing the water weekly is too much for your schedule, you can easily adjust and do the water change every two weeks while changing 20 to 25 percent of the water.

Do not forget to keep the conditions of the water column in doing regular water changes. But maintaining your water requirements can be difficult, but it needs to be done for the safety of the fish and the ecosystem. Also, you need to make sure that the water use in refilling the tank comes with a similar temperature and pH rating. You can do this by refilling lukewarm water when doing water changes in your fish tank.

clean fish tank without removing the fish

Cleaning Aquarium Water Filters

Often, aquarium owner fails to have a proper schedule when it comes to cleaning water filters. If you do not have one, I recommend cleaning the filter media at least once a month. You can also combine this process with a significant water change. It is also ideal for including vacuum gravel and cleaning your plants.

But, keep in mind that cleaning the filter does need to be done often. The reason behind it is that it ensures that the beneficial bacteria which will be responsible for purifying your water will remain intact.

Vacuuming the Substrate

The substrate on the aquarium is probably the dirtiest part of the tank since it harbors most of its dirt. So, it is essential to clean it regularly. The easiest way to clean the substrate is to use a gravel siphon kit because it is so easy to use. All you need is to pass the tube in the substrate to siphon all the dirt and debris away from the tank.

Meanwhile, the substrate can also assist in cleaning your tank with its properties. In fact, it also accumulates healthy bacteria over time. But this will only happen if there is excellent water circulation and oxygen found at the bottom of the aquarium. Vacuuming your gravel consistently can also help the good bacteria to thrive and dominate in the aquarium.

Bleaching your Plants

I feel that most aquarium owners believe the bleaching of your plants is not safe for your fish and the overall ecosystem of the aquarium. However, it is actually safe and is good in dealing with algae and other parasites in the aquarium. To do this, you will need to remove the plants from the fish tank and submerged them in a bleach solution of 19 cups water and 1 cup bleach. Leave the plants for about two minutes.

Then, you can transfer the plants into a bucket of room temperature water with a prime conditioner. You can do this rinsing process a number of times to completely remove the bleach solution away from the plants. You need to make sure are thoroughly rinsed before putting them back in the aquarium.


Learning how to clean a fish tank with fish in it is just one way to simplify the cleaning of your aquarium. Most often, aquarium owners stress the fish or the aquarium’s ecosystem by doing all the inappropriate things in cleaning the fish tank. However, you do not need to remove the fish in keeping your aquarium clean. All you have to do is follow all the hacks we have presented, and your aquarium will be healthier and cleaner.

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