How Often to Change the Aquarium Water?

How Often to Change the Aquarium Water

If you are an aquarist who enjoys maintaining a beautiful aquarium and like caring for their fish, you probably already know the importance of changing the aquarium water at the right time and doing it the right way.

However, it is not always easy to determine when it’s time to change the water in the aquarium. No wonder, “how often should I change aquarium water” is one of the most commonly asked questions among the fans of fish-keeping.

It is important to understand that you cannot just change the aquarium water whenever you feel like it. There’s a lot going on inside the aquarium and changing the water too early or waiting too long to do it can lead to disruption in the aquarium, which may adversely affect the health of your fish.

Keep in mind that water is as important to fish as air is to humans. Therefore, you cannot afford to be careless about it. Even a little negligence can lead to dire consequences for your fish.

This makes it important to take the time to learn about when and how to change aquarium water. From the size of the tank to the types of fish in the aquarium, there’s a lot that you need to keep in mind when it comes to determining the right time to replace the water in your aquarium. Scroll down to learn all about it!

When Should I Change Aquarium Water?

Are you waiting too long to change the aquarium water? Are you overdoing it? How often is too often anyway? All these questions often plague most aquarists. Fortunately, there are ways to determine the perfect time to change aquarium water.

Standard Water Changes

When it comes to changing the water in a well-established aquarium, the rule of the hand is to change around 10 – 20% of the water every week. This will maintain a balance in the aquarium.

The nitrate levels will remain low and in control. Your substrate will stay clean and free of debris and healthy bacteria will thrive inside the tank.

However, keep in mind that while these are standard water changes for a healthy aquarium environment, it does not mean that this the only time when you should change the water in your tank.

For instance, you should test the water regularly to find any unexpected changes and then replace the water accordingly.

Water Tests and Emergency Water Changes

Water tests are essential to establish and maintain a healthy water tank. You can perform water tests in your aquarium to keep an eye on the level of ammonia, nitrite, and nitrate.

If you notice an unexpected rise in their levels, get ready for emergency water changes. This is important because they are categorized as toxins and their presence in water can be lethal for your fish.

If the tests show high levels of ammonia, nitrates, or nitrites in the water, you can resort to changing the water daily or even twice a day until recommended levels are achieved.

The best approach is to replace 50% water twice in two separate water removal attempts. Once you have done that, change around 40% water every day until the ammonia level is reduced to zero. After that, you can continue changing the water according to the standard water changes.

Water Changes during Tank Cycling

Compounds like ammonia and nitrites are harmful to the health of your fish. If the level of ammonia and nitrite is not maintained at the minimum, your fish can become sick and even die. Surely, you don’t want that!

An easy solution to this problem is to maintain a cycled tank. A cycled tank can help you control the colony of nitrifying bacteria, which is responsible for the production of ammonia and nitrites in the water.

For this reason, it is important to cycle your tank to make it suitable for your fish. You should do it slowly over time and gradually introduce small and new fish into it. Cycling your tank is relevant to the frequency of changing the water in the aquarium because cycling involves regular partial water changes.

During tank cycling, your fish is being exposed to a lethal amount of ammonia and nitrate. To make sure it does not affect the health of your fish, you should change about 10 – 25% of the water every 2 -3 days.

Overdoing it may remove ammonia and nitrite that healthy bacteria need to establish inside the tank. In other words, if you change your aquarium water any more than required, your aquarium will not be cycled and your fish will suffer.

Water Changes for Sick Fish

When one of your fish friends falls sick, the first thing that you should do is shift it to a separate. There you can treat and medicate the sick fish without affecting the other fish in the aquarium. Some people believe that it is necessary to change the water for the sick fish daily.

However, this is not always the best idea. Doing so can render the medication ineffective as you will probably replace the water before the medication can affect properly.

The best way to deal with this problem is to carefully read the manufacturer’s instructions. Most medicines come with an elaborate explanation of how to use the medicine and in what quantities.

It is advisable to follow the manufacturer’s instructions and if you are still confused about the appropriate dosage or water removal, make sure to ask around the local fish supply shop.

Do it the Right Way!

Changing aquarium water the right way is just as important as changing it at the right time. There are certain things that you should take into consideration to keep your fish happy and healthy during and after the water changing process. It is important to understand that most fish are sensitive to change.

Even a slight disruption in the tank can stress them out. This makes it important to make sure that when you do change the water, you do it the right way.

Here are a few tips that can help you change the water without stressing the fish and maintain a healthy tank without much hassle.

Vacuum the substrate

When you are changing aquarium water, it is a good idea to vacuum the substrate to remove any detritus that may be building up at the bottom of your tank.

If you use sand as a substrate, rake it up with your fingers and use a siphon to take out water. Keep the siphon just half-inch above the sand to remove dirt, debris or any other impurities.

Mind the beneficial bacteria colonies

We know that healthy bacteria are important for a thriving aquarium. This is why when you are changing the water, you should take this fact into consideration.

Don’t remove too much of this beneficial bacteria as it will disrupt the chemical equilibrium inside the aquarium. An easy way to do that is to make sure there’s always some healthy bacteria in the aquarium is to clean the filter and gravel on different days.

Both these places are hubs to beneficial bacterial colonies so cleaning them on the same day may not be a good idea.

Always treat the water

Make it a habit to add only treated water into your aquarium.

Tap water contains chemicals like ammonia and chlorine, which are harmful to fish. This makes it absolutely essential to treat the water before introducing it in the tank.

Fortunately, a number of products are available in the market that can be used to treat and neutralize these chemicals. You can also consider using aged water for your aquarium.

Turn of the aquarium lights

Water changing is a stressful event for most fish.

Cleaning and water removal can create disruption in the tank which can easily stress out the tenants of your aquarium. Therefore, after a stressful water change, you can calm your fish by leaving the aquarium lights off for a few hours.

Fish are able to relax better in the dark and will feel less threatened.

DON’T clean your filter

Cleanliness is the key to a healthy aquarium.

However, it is important to understand that filters need to be dirty to work properly. So whatever you do, don’t keep your filters squeaky clean. It is okay to rinse the filters once a month while changing aquarium water but make sure you don’t overdo it.

Learn about your fish

While the general guidelines for changing aquarium water will work well for almost all aquariums, it is still a good idea to brush up your knowledge about your fish and tailor the water removal process according to its needs.

For example, some messy fish like large cichlids prefer large and frequent water changes. On the other hand, Tanganyikan cichlids will be more comfortable with around 10% water change at a time.

Changing and adding water is not the same

It is easy to believe that adding and changing water is the same thing. However, this is far from the truth.

Adding and changing water are two completely different processes. Adding water does not remove impurities from the aquarium. Even if you add water, you will still have to replace it.

Now that you know all about changing aquarium water, you can do it like a pro and keep your fish happy and healthy.

Remember, fish-keeping is a learning process and changing aquarium water is not an easy task. If you are a beginner, it may take some time but you will eventually get the hang of it.

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