To keep aquarium inhabitants healthy, you should always maintain all the water parameters on regular basis. In general, the water of the aquarium is influenced by several physico-chemical parameters. Among them, pH plays an important role to make the aquarium inhabitants happy and healthy. Maintaining a suitable pH level in your aquarium is the biggest challenge for any aquarist. Many beginner fish keepers cannot understand why it is necessary to maintain a stable pH level in an aquarium and what factors affect the pH level in an aquarium.
Why pH is important for your aquarium water?
pH can greatly affect the water in your fish tank and the value of it range from 0 to 14 in the pH scale. The pH of 7.0 is considered neutral, the values below 7.0 are acidic, and the values above 7.0 are alkaline. The pH of the water varies and depends on a number of factors, such as chemical concentration, mineral content, and type of substrate.
Each fish species is adapted to different pH levels. A pH value that will be normal for some fish may not suit other species at all. That is why it is very important to measure the pH level in an aquarium before releasing fish to it. In this case, you should always maintain a constant pH level. If you do not maintain a stable pH level, the level of ammonia in your tank will fluctuate. If pH level in your fish tank drops below 6.0, the bacteria that keep ammonia and nitrite in the tank begin to die off.
Total ammonia is the sum of ammonium ions (NH4+) and ammonia (NH3). Generally, the pH of the water is one of the most important factor which influences the aquarium inhabitants. More ammonia means more toxic which is generally present in alkaline water, while more ammonium ions mean less toxic that present in acidic water.
What Level of pH Should be in the Aquarium?
For considering the issue of pH, you should know what level of pH you will need to maintain in your aquarium. In general, the optimum pH level for fish is 7.0. Almost all fish build up a constant level of pH, which should be between 6.6 and 7.4. But a stable pH of 6.6 is better than a pH level that varies between 6.6 and 7.0. Saltwater fish like alkaline water with a pH of 8.0 or above while freshwater can live in the lower ranges pH which should between 5.5 and 7.5. Generally, it depends on the specific species. For example, freshwater aquarium fish such as discus loves to live at pH 7.0.
You should always keep in mind that the value of pH is not constant which changes overtime. Naturally, it rises during the daytime and drops at night time. Generally, Neon tetras are exceptionally sensitive to sudden changes in pH level. Because sudden changes in pH level in your tank can harmful or even deadly to fish. Breeding for many species of fish occurs only within a specific range pH. When the value of pH rises, it increases the ammonia level in the aquarium water which is very toxic to your fish.
Some fish species such as Discus and certain cichlid species can thrive in very narrow ranges of pH. In this case, you should be taken into consideration when setting up their aquarium.
Preferred pH Value for Some Common Freshwater Fish
| Fish Species | Scientific Name | Preferable pH Level |
|---|---|---|
| Freshwater Angelfish | Pterophyllum sp | 6.5 – 7.0 |
| Clown Loach | Chromobotia macracanthus | 6.0 – 6.5 |
| Freshwater Hachetfish | Gasteropelecus sternicla | 6.0 – 7.0 |
| Goldfish | Carassius auratus | 7.0 – 7.5 |
| Plecostomus | Hypostomus sp | 5.0 – 7.0 |
| Silver Dollar | Metynnis hypsauchen | 6.0 – 7.0 |
| Zebra Danio | Danio rerio | 6.5 – 7.0 |
| Neon Tetra | Paracheirodon innesi | 5.8 – 6.2 |
| Harlequin Rasbora | Trigonostigma heteromorpha | 6.0 – 6.5 |
| Tiger Barb | Barbus tetrazona | 6.0 – 6.5 |
Some Tips For Increasing pH Value in a Fish Tank
There are many options to raise the pH level in an aquarium. In this case, you can take the following some steps to raise the pH level in an aquarium.
Regular changing water: The level of pH value in your tank decreases due to overtime use of the same water. pH also decreases when you do periodic siphoning of soil from uneaten food and waste material. This process significantly lowers the pH value over time in your tank water. In this case, you should do regular changes of tank water to raise the pH level.
Adding stones, rock or gravel: To increase the pH level, you should add stones, rocks, gravel or snags to the aquarium. Generally, crushed corals are used as a substrate in aquariums to increase the pH level. You can also use limestone and petrified corals to increase pH. In this case, care should be taken to add stones, rock or gravel because this method may increase the value of pH level significantly than the acceptance level causing fish mortality.
Aeration: For increasing the dissolved oxygen (DO) concentration in your tank water, you should use an aerator. Because high concentration of DO serve to lower the CO2 concentration and helps to reduce the pH level. A smaller amount of carbon dioxide (CO2) leads to a higher level of pH.
Adding Baking Soda: You can also add baking soda to raise the pH level in your fish tank. In this case, you have to add soda in your tank all the time. During adding soda, careful measures should be taken because adding much soda cause a spike in pH which can harm your fish. Generally, 1 teaspoon soda per 20 liters of water is needed. In this case, soda must be dissolved first in a small amount of water before adding it to the aquarium. After dissolving soda then you should pour it into the aquarium.
Adding salts: To boost up pH level, you can also add sodium and potassium salts with a dose of 1 teaspoon soda per 20 liters of water. At present, in the pet market, pH enhancing products are available with sensible cost. Among them, API pH UP Solution or Tropic Marin Triple-Buffer can quickly raise the pH level to 8 units. You can also use Tetra pH / KH Plus which are very popular and they are very safe for fish and plants.
How to Lower The pH in an Aquarium?
There are some options for lowering pH value in your aquarium that you can try. Generally, reducing the pH in a freshwater aquarium is often difficult than raising it. You can do it following different ways:
Using peat moss filtration: Peat moss filtration is the most effective way to lower the pH value in the aquarium water. You can also use peat moss in your aquarium as a substrate, which has a similar effect.
Adding carbon dioxide (CO2): If you increase the concentration of carbon dioxide (CO2) in water which makes acid and ultimately lowers the pH value in your aquarium.
Adding Snags: Many types of snags are used to decorate the aquarium. Most of them reduce the pH level and you can use it.
Applying Chemical substances: In the pet fish market, there are many chemicals today that lower the pH value. You can purchase such type of chemicals with sensible cost and lower the pH level by adding them to your aquarium water.
Also Read: How to Maintain Ammonia Level in a Goldfish Tank
Final Words
The pH of the water in an aquarium significantly affects both its quality and chemical composition. Hence, it is much more important to maintain a pH level in your aquarium. Generally, aquarium fish prefer the pH level like the natural environment. Constant maintaining of the pH level in your tank will not lead to anything good since pH fluctuations of only 0.3 units can be dangerous for fish. In this case, you should measure the value of pH on regular basis. It is the best way to measure the pH level using the water testing kit. You can purchase one of the kits at your local pet store or order it online.