How can you lower the pH of your fish tank?
About 85% of American homes have hard water with a pH that’s far too high for most aquariums.
Bottles of pH adjusting chemicals abound at every pet store, but a more natural approach is usually better. Natural methods of adjusting pH maintain a more stable pH level that doesn’t rise and fall with each water change.
Sudden changes in pH can be incredibly stressful for all aquarium life, so, for the health of our fish, let’s do it naturally!
How To Lower pH In Aquarium
The perfect pH will be different depending on the types of fish you are keeping. For example, the best pH for discus fish is 6.5, while the best pH for a salt water aquarium is between 7.6 and 8.4.
Whatever your case, if you want to lower the pH of your aquarium, here are the 3 best natural methods.
1. Using Driftwood To Lower pH
Driftwood is one of the most attractive, simple, and long-lasting ways to lower pH in the aquarium.
The pieces look lovely in the home aquarium but serve multiple purposes. Not only do they lower pH, but they also act as a filter, removing contaminants from the water. The more course or porous the piece, the better it will be as a pH altering agent.
The downside of using driftwood in the aquarium, is that it has the potential to leave the fish tank water discolored.
The tannin in the wood can discolor your water, but this is also what lowers the water pH. Keep this in mind when deciding how to manage your home aquarium.
A piece of driftwood will certainly lose efficacy over time. While always maintaining some pH lowering effect, it is most potent in those first couple of months after you install it.
Discoloration, as you’ll soon find, is a side effect of most pH reducing compounds. With driftwood it can be mostly avoided by boiling the piece until the water runs clear. This usually just takes a few minutes, depending on size.
The catch 22, is that the longer the piece is boiled, the less effective it becomes at lowering the pH. So be careful not to overdo it!
Be careful when purchasing pieces of driftwood at pet stores: raw wood that’s been boiled or soaked is perfect, as is anything intended for the aquarium. But pieces that are labeled exclusively for reptiles can be toxic for fish.
Driftwood, and other porous decor, intended for reptile habitats are usually chemically treated. This makes it easy to rinse clean, and to withstand the rays of heat-lamps. These chemicals can be deadly for fish, so make sure you choose aquarium driftwood.
Bonsai Driftwood specializes in decorative driftwood for the aquarium with a wide selection of absolutely beautiful pieces all with the benefit of Amazon Prime’s shipping and customer service.
2. Lowering pH With Peat Moss
Peat moss (which includes Sphagnum moss) is extremely efficient at softening aquarium water and bringing pH levels down.
However, like driftwood, it too can discolor the water. To avoid this discoloration, simply soak the moss in water for a few days, changing it occasionally until it runs clear.
Initially, peat tends to yield a strong yellow color. The results are well worth the preparation though, just place the peat moss into a filter bag and drop into your existing filter. The pH change is long-lasting and gradual enough that fish stress isn’t an issue.
Fluval has a great reputation for its high-quality aquarium products. These granules are ideal for canister filters, but can be placed in a hang-on-the-back filter as mentioned above.
These water softener pillows are also very affordable and easy to use. They achieve the same thing as the Fluval granules, using peat.
3. Almond Leaves
Most community aquariums contain what are commonly known as “black water” fish.
The water of their natural environment is a deep brown color that’s created by the tannin and compounds leached from the trees growing along the river and the leaves and debris that fall to the bottom.
The Terminalia catappa tree, also known as the Indian Almond, has been hailed as nothing less than a miracle in many aquarium communities. Some aquarists insist that these leaves are an absolute necessity for breeding bettas or Angelfish and even that they can even bring fish back from the brink of death.
Although some of the claims made about them are a little dubious, these leaves definitely excel at improving water conditions. Adding a few dried Cattapa leaves work to enrich the fish tank’s chemical parameters all around, softening the water and naturally bringing the pH down.
There’s an abundance of naturally protective chemical compounds in Indian Almond leaves. These are said to protect the tree from bacterial and fungal infection in the humid environments of its native Southeast Asian environment.
These antibiotic and antifungal properties have some obvious benefits for the aquarium ecosystem as well. But the benefits must be balanced with the side effect of not having crystal-clear water. The perfect balance is of course entirely up to the individual aquarium keeper.
The best advice with this method is probably just to add one leaf a day until you’re happy with the water clarity (or lack thereof). More leaves will need to be added with future water changes and it’s best to vacuum up old leaves once they begin to deteriorate.
If the water is still too alkaline, combine this with another method.
Dried indian Almond leaves are affordable and readily available:
Raising Aquarium pH
If you’re one of those lucky few with perfectly soft, slightly alkaline water, raising the pH is very simple and the ingredients are probably already in your kitchen!
Simply add 1 tsp of baking soda per 5 gallons gradually over the course of a week or two and with each water change.
Limestone is also extremely efficient at increasing the pH. It’s also a permanent choice that requires little to zero maintence. African Cichlids require a high pH and love hard water: one of the many reasons that cichlid tanks are usually filled with limestone décor.
Good luck in your journey to achieve the perfect aquarium; full of happy, healthy and long-lived fish!
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