Home Brands Products Deals Promo Finder Store Features Forums Add Review What's Knoji? Sign Up Login

How to Acidify the Water in an Aquarium

Knoji reviews products and up-and-coming brands we think you'll love. In certain cases, we may receive a commission from brands mentioned in our guides. Learn more.
In order for the fish to survive and grow well, it is important for the aquarist to adjust the level of acidity of the fish tank. Learning how to acidify aquarium water can definitely affect your pet's survival.


Wikimedia Commons / by Serge TalferAcidity level is very important in maintaining your aquarium. Aside from other factors, it also plays a big part on whether your pet fish will survive or not. Thus, knowing how to acidify the water in your aquarium is very vital.

Some tropical fish for example are very particular when it comes to the level of acidity of the water in the tank. A proper level is helpful especially in the breeding process of the marine animals in your tank.

Water acidity or water softness can be measured through its pH level. Neutral levels like tap water has a pH of 7.0. Greater than this is considered basic or alkaline, while anything lower than 7 is considered acidic. Most freshwater fish can thrive within 6.5 to 8.5 pH levels; others may need more acidity of soft water than neutral.

In most cases, a higher pH level can harm your fish, hamper their breeding process or eventually kill them. This is why, maintaining proper levels is very important.

Ways to Acidify Aquarium Water

There are ways to acidify the water in your tank. There are natural ways to do it or you can buy commercially available products that can soften the water.

1. PEAT FILTRATION - This is the most common method. It uses peat granules that release tannic and humic acids into the water that make it soft or acidic. This compound makes the water tea-colored and resembles a blackwater condition. This method is particularly excellent for blackwater fish like neons, harlequin rasboras and cardinals, However, peat filtration can hamper the growth of other living things inside the aquarium since light can not penetrate well in a dark environment.

2. WATER PURIFIER - This eliminates the alkaline minerals in the water and can make it soft. It can be used by changing 50 percent of the water in the tank every three days until the desired pH level is reached. Water purification can remove substances in the water like pesticides, bacteria and heavy metals. It can be done through reverse osmosis or boiling tap water.

3. RAINWATER - Rainwater usually has a neutral to slight pH level and some aquarist collect rainwater for their aquarium. However, make sure that the collected rainwater is free from toxic materials and the area is not an industrial site, where heavily polluted rainwater is very possible.

4. DRIFTWOOD - Another natural way to acidify your water is by putting unprocessed driftwood in the tank. Just like peat, it also releases tannins into the water and helps in making it soft or acidic. Driftwood can be obtained commercially.

5. COMMERCIAL ADDITIVES - There are commercially available products that are used by some aquarist in acidifying their tanks. For example, a "pH down" product has weak acids that can lower pH levels. But then, this has a short term effect and the water condition may return to a normal state after its effect expires. You may need to apply it on a regular basis to keep it working. Some commercial additives however, may pose negative effects on the life inside your aquarium and should be used carefully based on instructions.


About This Article

Marky Chavez

Explore Top Fitness Equipment Brands

Expand more
Top-ranked fitness equipment brands