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How To Safely And Naturally Lower The pH Of Your Aquarium

Maintaining proper pH is invaluable when it comes to raising healthy, happy fish. Many people spend all of their time focusing on the temperature of their tank, but really, pH plays just as vital a role.

Unfortunately, if you don’t know how to adjust the pH in your aquarium in a natural way, this can cause a ton of stress for your fish. Understanding exactly what pH is – as well as how to safely lower the pH in your tank, can make for a much more pleasant experience for everybody involved.

pH Of Aquarium

What Exactly Is pH?

You might remember some conversations about pH from your high school science days. If you don’t, the basics are pretty simple to relearn. When you think about water, remember that it is made out of oxygen and hydrogen molecules. Those molecules split up, with some losing hydrogen and hydroxide ions.

In pure water, there will be an equal number of hydroxide ions and hydrogen ions. However when an alkaline or acidic material dissolves in the water of your aquarium, the balance of ions is changed – thereby changing your pH.

And this is easy to do. pH is easily changed by food particles, fish waste, and other elements that you have little control over. While an acidic substance will increase the amount of hydrogen ions, lowering the pH, a basic one will raise the pH in your tank.

You can measure acidity and alkalinity on the pH scale. A strong, acidic solution will have about a hundred trillion more hydrogen ions than a basic one. To make it easier to understand, scientists invented the pH scale that operates on a scale of 0-14. 7 refers to the neutral rating, while lower is acidic and higher is basic.

Every number on the pH scale represents a difference times ten – for example, if your aquarium has a pH of 6, this means that it is ten times more acidic than a tank with a pH of 7. So what may seem like a small difference in the readings can actually be a major difference in the long run.

Why Do I Need To Lower The pH In My Aquarium?

In most cases, you won’t need to lower the pH in your fish tank – most aquariums do well at a neutral reading of 7 or 8. However, you might decide that you want to lower your pH if your fish start to appear sick or have low energy. You may have been able to confirm that pH was the cause.

Alternatively, some fish and some types of plants simply thrive at a lower pH level.

How To Lower The pH Levels In Your Aquarium

It is best to attempt to lower the pH in your aquarium by using the most natural methods that are available to you. While there are strobe light chemicals that you can use to do this job for you, these tend to alter pH more quickly than is natural, which can harm the health of your fish and cause illness or potentially even death.

Here are some safer alternatives for you to try.

1 Clean Your Aquarium

This is the first step you should take when the pH is off in your aquarium – and this applies to both aquariums that are overly acidic and not acidic enough. While increasing the pH of your tank is often easier than decreasing it – because minerals can be hard to remove – cleaning is a good first step.

Here’s why. If you can reduce the amount of ammonia in your tank – which is usually the chief culprit behind an increased pH – you can reduce the pH. Cleaning the tank helps get rid of fish waste (which creates ammonia) as well as leftover food. Makes sure you clean your gravel, too, to remove any debris. Clean your decorations without using soap or detergents.

You should also conduct a water change of 10% every day. Alternatively, you can replace 30% of the water every 5 days.

2 Peat Moss

Peat moss is a fantastic way to lower the pH of your aquarium and it will also help filter out contaminants the tank. Unfortunately, because of its dark brown-yellow color, it can easily change the color of the water in your tank.

You can combat this by soaking the moss in a bucket for a few days prior to putting it in the tank. This will reduce the discoloration that occurs. Keep in mind that when you add peat moss to your tank, you will need to leave it in there for quite some time in order for it to make a difference to the pH of your tank. Simply dipping it in the water and then taking it back out won’t do much to help.

Peat moss works by releasing gallic and tannic acids into the water. These acids go after the bicarbonates that are found in alkaline tanks, reducing the overall hardness and pH of the water in the process.

While There aren’t any set guidelines as to how much peat moss you should use – this will depend on the current pH of your tank as well as the type of peat moss and size of the tank – you can start off with a small clump of peat moss and simply keep an eye on it. This will let you observe whether it is taking effect or if it needs more time to be successful.

3 Driftwood

Driftwood is another great alternative to lower the pH of your fish tank. Unfortunately, like peat moss, it can also change the color of your water. It won’t cause any danger to your plants or fish, but it can stain your water a dull brown or yellow color.

Only add driftwood if you have fish species that will enjoy being around it – there are some fish that particularly love having driftwood in the tank because it gives them a place to hide and to play. However, it can stress some fish.

You need to make sure that you only pick driftwood that is designed for aquarium use. Don’t pull some off the beach and think it will be safe to use in your tank! Instead, you should look for driftwood that is sold specifically to be used in aquariums. You can also find driftwood that is designed for reptile tanks, but again, this kind of driftwood can contain dangerous chemicals that don’t harm reptiles, but do affect the health of your fish.

Make sure the driftwood you select is clean, and remove any built-u debris or dirt. Boiling your driftwood in saltwater can sterilize it and it will also help reduce the effects of discoloration that the driftwood might have in your tank.

4 Upgrade Your Filter

If it’s been a while since you rethought your filtration system, now might be the time. A filtration unit that is the wrong size – or one that doesn’t work properly – can easily affect the pH in your tank. You might want to upgrade to a larger filter. Make sure you clean it regularly to remove debris, taking care not to remove the buildup on the biofilter – instead, rinse it gently with water to eliminate clogs.

5 Avoid Changing the Substrate and Decorations

If you like to frequently redecorate your fish tank, this could be partially to blame for your new lower pH. Whenever you add anything to your tank, it plays a role in the conditions of the water. If you change the gravel, make sure you have the proper type for your fish. As an example, crushed coral is great to look at, but it can harm those fish who require a lower pH.

Some other decorations, like shell and rock, can leak dyes or minerals into the tank. This can not only raise the pH of the water, but it can cause a toxic reaction that can sometimes kill your fish. Be careful about anything you add to your tank.

6 Reduce Aeration

If you have a lot of oxygen in your tank, you will have more carbon dioxide, too – and this will lower pH levels. You can easily lower pH in your fish tank by reducing aeration. Remember that this can be tricky to do, as some fish require specific amounts of oxygen to survive. Follow this tip delicately and make sure you don’t change things all at once.

7 Consider Using Chemicals

There are some chemicals that can adjust the pH of your tank, but this is not always recommended. Chemicals are easy to add, but they can be very strong – even one drop that is higher than the recommended maximum amount can kill your fish. They can also cause your more vulnerable fish to be more susceptible to illness. Chemicals should only be used as a last resort.

8 Try Vinegar

Some people add vinegar to their fish tanks to help lower pH. It works in two separate ways. First, the vinegar contains acetic acid which will release hydrogen ions through a process known as ionization. The bacteria and other microorganisms in your tank will metabolize this acetate, using some of the oxygen in the process. If you decide to add vinegar, you need to be careful about adding too much.

9 Indian Almond Leaves

Indian Almond Leaves, or Catappa, are another great solution to naturally lower the pH of your tank. These leaves will decompose slowly in your tank, releasing tannins as they do so. You can either soak the leaves overnight and add the stringed water to your tank, or you can add the entire leaves.

There aren’t a lot of poor side effects to using Indian Almond Leaves, although he will discolor your water. Soaking can reduce the amount of color change that happens, but remember that the discoloration won’t harm your fish in the slightest. Another good benefit of using this solution is that Indian Almond Leaves have profound antibacterial properties, meaning they can help you get rid of certain diseases in your tank.

10 Use Reverse Osmosis

Reverse Osmosis is the process of purifying water by using a semipermeable membrane. This membrane allows only very fine molecules of water to pass through, which filters out nearly 99% of water impurities like arsenic, pesticides, heavy metals, and toxins. This will allow you to maintain a stable pH level at all times.

However, Reverse Osmosis units can be quite expensive – up to several hundred dollars, in some cases. That being said, this process is incredibly safe and it won’t discolor the water in your aquarium. If you find that you are constantly needing to lower the pH of your tank, a Reverse Osmosis unit might be a good investment – particularly do you have naturally hard tap water.

11 Monitor the pH

If you’ve been having problems with pH in your fish tank, you need to be vigilant about the parameters of your water. This is particularly true if you have just added new fish to your tank – adding anything new to the aquarium a cause a fluctuation in pH.

How To Keep pH Stable

Keeping your pH stable is always better than allowing it to fluctuate. There are several tips you can follow to keep things level.

First you should make sure that you clean your aquarium every other week. This will help to prevent a buildup of ammonia and nitrites in the water, both of which can cause an increase in pH readings. You should remove any algae that has accumulated on the walls or decorations of the tank. Then, make sure you replace about 10 to 15% of the water in the tank and use a siphon to clean the gravel and harder-to-reach decorations.

You should also invest in a high-quality filter. This will help remove toxins from the water that can elevate your pH and make your sick fish. Don’t just install a filter and leave it there, either – make sure you check it regularly to ensure that it is functioning properly. It will also need to be cleaned on a regular basis.

Finally, be sure to test the pH of your aquarium at least once a month. You can purchase a pH test kit that is specifically designed for aquariums at your local pet store. Make sure the pH is as close to possible as what your fish and plants need, but if it is not ideal, don’t change it rapidly – change it gradually over time.

Why You Need To Keep Things Stable

While it’s important that you try to match the perfect pH needed for your fish, it’s more important that you keep the levels in your tank stable. Just because the optimal pH for your fish is 6.0, that doesn’t mean that you need to stay exactly at 6.0 at all times, particularly if your water has a natural tendency to want to stay at 6.5.

The reason for this is that fluctuations in pH, whether intentional or unintentional, can cause some serious harm to your fish. What may seem like a small fluctuation can seriously stress your fish and increase the likelihood of injury or disease.

Instead, try to remain consistent. Incorporating one of the solutions above can help adjust the pH of your water to a lower measurement in the meantime, but remember that staying stable is always better than trying to achieve the “perfect” pH.

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