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What Causes High pH In An Aquarium? Everything You Need To Know

how to clean a tank without losing bacteria

What Causes High pH In An Aquarium?

When it comes to maintaining your aquarium, keeping it clean and changing the water on a regular basis are not the only things to consider. Rather, you need to understand what causes high pH in an aquarium and how you can achieve an optimal pH level in your aquarium.

You can certainly do this by controlling the concentration level of different substances in your aquarium. But being fully equipped with the right information is important to get these things done in a more effective way.

Do you want to know what causes high pH in an aquarium and how you can control it in the best possible way? Let’s have a look at the different pieces of information given below to get a better idea.

So, here we go:

What Causes High pH In An Aquarium?

how to monitor pH levels

Before reading on, it’s important to know the pH scale.

  • Acidic: 1-6.9
  • Neutral: 7
  • Alkaline: 7.1-14

When it comes to maintaining a healthy aquarium to ensure a high quality of life for your aquatic pets, maintaining an optimal pH level in an aquarium is important. However, many people don’t know what causes high pH in an aquarium.

So, here we have a list of some of the most important things to let you know what causes high pH in an aquarium.

  • Depletion of carbon dioxide can be what causes high pH in an aquarium.
  • Adding tap water to your aquarium on a regular basis can also lead to higher pH levels.
  • Untreated water from ground sources, including boreholes in your aquarium, can increase the pH level. Rainwater, water from boreholes, streams, etc., are pretty high in alkaline or acidic levels.
  • Addition of alkalinity supplements into an aquarium can also lead to a sharp increase in the aquarium’s pH level.
  • The food you are adding to your tank on a regular basis can cause a sudden increase in the pH level in an aquarium.
  • The depletion of aquarium plants can cause carbon dioxide levels to drop in an aquarium, which can also cause a steady increase in pH levels.
  • The fish food and fish decoration addition in an aquarium can also cause an increase in alkalinity
  • Fish waste materials can increase pH levels. It is highly important to deploy a filtration system inside the aquarium to eliminate fish waste materials in the best possible way.

So, these are some of the most important things you need to consider when understanding what causes high pH in an aquarium. These things can give you a better idea of maintaining an effective pH level in your aquarium in the most effective way. 

What Is The Optimal pH For An Aquarium?

Well, this is something that many people want to know. So, the most recommended pH level in a tropical fish aquarium is from 6.8 to 7.2. This is important when you are keeping a variety of tropical fish in your aquarium.

However, some types of fish species should be kept in separate aquariums due to their high pH requirements, such as mollies and swordtails that require 7.2 to 7.5 pH levels to thrive and Goldfish that need to be kept at 7.5 pH to thrive.

It’s important to know that there can be different requirements for different species in an aquarium. Therefore, the exact optimal pH level may vary accordingly.

How To Test The pH Of Aquarium Water

How to test pH levels in an aquarium

Testing the pH level of water in aquariums is important to ensure an optimal pH range. However, if you don’t know how to do it, then use an aquarium test kit. This can be one of the most effective ways to find the pH range of an aquarium. For this, you can add some water from your tank to the test tube.

Then add a drop of the testing solution and observe the change in color to identify whether the pH level is low or high in the aquarium.

You can also use pH litmus strips to test the pH of aquarium water.

How To Lower The pH In Your Aquarium

When you understand what causes high pH in an aquarium, you must try to learn the best ways to reduce pH in your aquarium as well.

Do you want to reduce your aquarium’s pH level to keep your fish and other aquarium members healthy? Let’s have a look at the options below to know more about this:

Osmosis filter

Using an osmosis filter is one of the best ways to reduce the level of pH in water as it contains some chemical substances which are effective in reducing ph. Using an osmosis filter to lower an aquarium’s pH can be considered a long-term approach to maintain a well-balanced pH more effectively.

Add natural stuff to the aquarium

Add one or two natural driftwood pieces to your aquarium. This can act as a natural filter inside your aquarium. Driftwood doesn’t contain any dyes, preservatives, or other types of chemicals. Two pieces of driftwood are enough to keep in any aquarium size.

However, it is highly important to avoid any manufactured driftwood. This is because manufactured driftwood may contain chemicals.

Also, make sure to boil driftwood before you add it inside a tank. Otherwise, it can cause coloration.

You can leave driftwood inside your aquarium for a longer period of time to let it filter the aquarium water naturally.

Natural peat moss

Natural peat moss can also play a vital role in lowering the pH level of water in your aquarium. However, you need some time to prepare this natural substance before putting it in your aquarium.

  • Get the peat moss from any of the nearest pet shops but ensure that it is meant to be used in a fish aquarium and is 100% natural as well.
  • Soak this peat moss in clean water for about 4 days before putting it in your aquarium. This is important to keep your aquarium water from turning brown or yellow.

However, when you put peat moss inside the aquarium, make sure to use a filter bag. This will keep it from floating.

It is recommended to add peat moss to the aquarium water in small quantities for a slow reduction in the water’s pH level.

Almond leaves

Natural almond leaves can be an amazing addition to your aquarium to reduce the pH level of water. These are not only effective in reducing pH levels but can also work well in preventing multiple diseases due to their anti-inflammatory properties.

Almond leaves also look aesthetically appealing and can offer plenty of space for your fish to hide in the aquarium. Good almond leaves can be found at any local pet store.

Clean your aquarium regularly

Cleaning your aquarium on a regular basis can also play a vital role in lowering the pH level of your aquarium.

Symptoms Of High pH In An Aquarium

platy fish

Here are some of the most important signs to understand symptoms of high pH level in an aquarium:

  • A sudden increase in the growth of green algae on the ornaments and walls of the tank can make the water toxic for fish.
  • Unusual behavior of fishes can be due to high pH. You can see excessive excitement and chaotic swimming when the pH levels are high in your aquarium.
  • A diseased fish is an advanced symptom of the high pH in your aquarium.

If you are noticing any of these symptoms, you may want to try lowering the pH in your aquarium.

How To Raise pH In An Aquarium

A drop in the pH level of an aquarium can be problematic. Therefore, it is also important for you to know the best ways to increase pH in an aquarium.

Here are some of the quick-fix options you can consider:

Aerate the water

You can raise the pH level in an aquarium by increasing dissolved oxygen concentration in water. Doing this can lower the Co2 concentration in water. The simplest solution to do this is by placing a filter outlet above the water’s surface.

Change the water

The pH level of the aquarium can gradually lower due to the buildup of pollutants in it. You can consider changing water to get an effective pH level.

Baking soda

Baking soda that can be found in almost every kitchen can also help in raising pH in aquariums. Adding a small amount of baking soda to the aquarium can result in a quick rise in aquarium’s pH level.

Change the substrate

Some amazing materials that can help you raise the pH levels in aquariums. Adding these materials can be an easy solution. Some of the best options include petrified coral, crushed coral, certain shells, and limestone.

Keep checking your aquarium’s pH level regularly and treat it as needed to achieve the optimal pH level in the aquarium.

Factors That Can Affect The pH In Your Aquarium

Celestial Pearl Danio

Here are some factors that can affect the pH level in your aquarium:

  • Changing the water
  • Decreased aeration
  • Adding driftwood can low pH
  • Waste and pollutants in water
  • High level of nitrates
  • Hard water in your aquarium
  • Use of water purifier
  • Overstocking the aquarium

So, these are some of the most common factors which can lead to variation in pH level. Stability in pH level is important.

How Often Should You Test The pH Level In Your Aquarium?

This is one of the most common questions asked by fishkeeping beginners.

  • It is important to check your aquarium’s pH level after a fish or one of your other aquatic pets get sick or die.
  • If your aquarium has been treated with medicine, it is highly important for you to check the aquarium’s pH level at the time medication is starting and on the last day of treatment. Make sure to check the pH level of the aquarium even after one week of medication.

However, if the water pH level is varying from your aquarium’s optimal pH level, then you should think about changing the water.

Why Is pH Important?

The video below provides an in-depth look at pH and why it matters in aquariums:

Maintaining an optimal pH level of aquarium water is highly important to avoid the side effects of high pH in aquariums. However, pH inside the water is important for multiple reasons, including:

  • Identifying the amount of oxygen your fish are getting inside the aquarium water to thrive.
  • A lower pH of water means fish are getting a larger amount of oxygen, while higher pH means there is less oxygen in the water.
  • High pH in the water can lead your fish to have depleted energy. So, you must test the pH and bring it to optimal level if it is too high or too low.
  • A high pH level inside the aquarium can make it alkaline and can pose a serious threat to your fish as well as its environment.
  • Changing in pH level can make your fish slow down their activities or lead them to illness.

Keep checking the pH level of water in the aquarium to ensure a healthy environment for your fish and other aquatic pets as well.

How To Monitor pH Levels

When you decide to buy a new aquarium, it is highly important to closely monitor its pH levels. You can pay attention to the behavior of fish in the aquarium.

Young fish will struggle if pH levels in the aquarium are off. Even more, some of the fish species also contain a tight pH range. Some fish are not going to reproduce if pH levels in the aquarium are off.

If you observe any behavioral change in your fish inside the aquarium, it becomes vital to test the pH level.

If the numbers are too high, then make sure to adopt natural strategies to reduce the pH levels of water in the aquarium.

You can also monitor the pH levels of water in the aquarium while adding a new fish to it. Test the water both in the aquarium and the fish’s bag and make any required changes.

Can Plants Lower The pH In A Tank?

20 gallon tank

Plants can either decrease or increase pH in an aquarium in different ways. It completely depends on how you are going to control their activities. However, it is a vital factor to consider that carbon dioxide can decrease pH levels in the aquarium, while carbon alone would have no effect on this.

  • Plants can increase the pH level of water in the aquarium as they reduce carbon dioxide.
  • Thus, the elimination of CO2 from the water can cause a rise in pH level of the water in the aquarium.
  • However, it is important here to understand that even the effect of removing CO2 from water is small, but the effect on the pH levels will be steady.

However, there are multiple other compounds that plants can metabolize, which can affect pH levels as well. For example, plants can absorb nitrogenous substances and ammonia. These Nitrogenous substances will trigger different biological processes that can develop free hydrogen ions to reduce pH.

The absorption of more nitrogenous substances will create more hydrogen ions that will be released in the water, which will lower the pH levels in an aquarium.

Even though dead plants can lower pH levels in an aquarium, they are never recommended to keep in your aquarium. This is because dead plants inside the aquarium are not safe for your fish and other aquarium inhabitants.

  • Therefore, it is highly important to remove dead plants and change your aquarium’s water as quickly as possible when you find a dead plant in it.
  • Overall, it is highly important to understand which plant species can increase or decrease pH in aquariums before keeping them inside.

This will help you in maintaining an optimal pH level in your aquarium in the best possible way.

Conclusion – What Causes High pH In An Aquarium?

Many fish and other aquarium members perform well in a low pH level of water in an aquarium. However, it is highly important to not let your aquarium water become too acidic. Water that is too acidic could have adverse effects on your aquatic friends.

It is highly important to understand the optimal pH level of your aquarium for your chosen species. This is so that maintaining an effective pH range can be easier for you.