How to Lower pH in Fish Tank? It’s just impressive to have a home fish tank and it is very nice to keep the pets happy all the time. The water quality in your fish tank must be maintained for them to live happily.
Since they are living organisms, their pH level of their body fluids need to be alkaline but not like ours; which must be neutral or slightly acidic. They prefer a more alkaline environment, which has a pH range between 7-9. When this balance gets out off hand then you’ll see some health issues in your pet fishes such as stress, illness and even death. Hence keeping an eye on PH levels is very important especially when there is drastic change over time.
What is the ideal pH for an Aquarium?
The ideal pH level for your aquarium is between 7.2 and 8.4, as this range will keep your water clean and stable so that you fish are safe in their environment. You can monitor the PH level at home by using test kits which are available in the market over-the-counter or via online shopping sites like Amazon .
How to lower the pH in your Aquarium?
1. Perform Partial Water Change Regularly
Performing partial water change regularly is one of the most simplest way to lower ph level in an aquarium. If you live close to a lake or river, then your tap water is probably of neutral pH level. Using it often will affect the alkalinity of your fish tank and lower off the PH levels, which is not good for them. If you must use tap water, keep using it but only when performing a 40-50% partial water change in between other freshwater sources.
2. Get a New Filter
An old canister filter can also contribute to higher levels of pH in your aquarium; as they suck up both dissolved CO2 (carbon dioxide) from the atmosphere and H20 (water). The carbon dioxide that is absorbed by the cartridge during filtration will increase the alkalinity of water thus creating acidic environment for fishes  . There are many good quality canister filters available in the market with an adjustable pH control option, but make sure that you should change it once every 3 months to maintain optimum water quality.
3. Add Peat Moss
Adding peat moss is also a good idea for lower ph level in your aquarium; as it helps to buffer the alkalinity of water by releasing CO2 through microbial activity; which aids in lowering down its pH  . You can add 3-4 pounds of dry peat moss per 20 gallons of fish tank water daily till desired results are achieved. Always monitor your fishes and do partial water changes whenever needed. Some hobbyist says that adding pieces or whole of Almond leaves/Catappa tree in your aquarium will help to lower pH level by releasing CO2 gas as well.
4. Add Driftwood to the Aquarium
Driftwood can help in lowering your fish tank’s pH levels; it will develop a natural acidic environment over time, which is beneficial for fishes  . Adding driftwood will also provide a hiding place and habitats for your fishes too. It is also believed that water-soaking basking rocks made out of lava, limestone or marble have similar effects on low pH levels in aquariums as they release H+ ions into the water system; thereby accomplishing the goal of lowering pH  .
5. Add Almond Leaves/Catappa Tree
Almond leaves/Catappa tree are considered good for the environment; as they are known for their antibacterial, antiviral, antifungal and anti-inflammatory properties. They also help to remove ammonia and nitrites from aquariums; thus adding a good health value of fish living there  . However if they are not available near your house then try adding few pieces or whole branches in your aquarium and let it sit there overnight accordingly.
6. Reverse Osmosis
Using reverse osmosis is also one of the best option to lower pH level in your aquarium water; it will stop all types of dissolved solids that may affect the alkalinity of water negatively which results in acidic condition. This machine will concentrate ions like CO2 (carbon dioxide) by pumping them out of the fish tank; thus lowering down the aquarium’s pH level  .
7. Decrease Aeration in the Tank
Decreasing aeration is another good idea to lower pH levels in your fish tank; as it will also reduce dissolved oxygen (DO2) rate and promote CO2 production due to increased microbial activity  . The more time that passes by, more carbon dioxide gas will be produced by peat moss or driftwood piece/branch and you can monitor your fishes for any negative effects on them to avoid further problems.
8. Wrapping up:
Lowering pH in a freshwater aquarium is one of many ways that hobbyist use regularly to maintain optimum water quality for their aquatic life. Perform partial water changes often with reverse osmosis to remove carbon dioxide and other dissolved solids from your tank; this will help decrease the alkalinity level in water making it acidic instead. Adding a new filter with adjustable pH control option is also more economical than going for costly methods of lowering pH levels.