Causes of high pH in your Fish Tank

  • Aquatic Plants -  If you have Aquatic plants, they can trap Carbon dioxide and other materials like nitrates.
  • Stones and Rocks - Certain stones and rocks can raise your Water's pH levels. Calcium-rich materials like limestone dissolve and mix into the water, thus increasing the pH.
  • Tap water - It contains alkaline compounds and metals. This is why most experts will recommend against using regular, unconditioned tap water in your aquarium.

What is pH?

The letters pH stand for the "power of hydrogen". Since capital H is the chemical symbol for hydrogen it is always written as "pH". The pH is a measure of hydrogen ions in a solution.

Symptoms of high pH in an aquarium

Fish Symptoms

One of the most obvious signs that your aquarium's pH is too high is that the fish are behaving unusually. Fish suffering from alkalosis (illness caused by high pH ) will exhibit excessive excitement, swimming quickly; some may try to jump out of the tank or purposefully scratch themselves on rocks in the aquarium. Fins will be spread wide, and the gills may secrete mucus. The fish may also appear sluggish and their breathing may be labored.

Environmental Symptoms

The aquarium itself will often reveal signs of high alkalinity as well. You may notice a sudden increase in green algae growth on the walls and ornaments in the tank. High pH levels encourage the growth of this algae and slime, which will thickly coat the plants and fixtures, Making the water highly toxic for fish.

What happens if the pH is too high

A sudden increase in green algae growth on the walls and ornaments in the tank. High pH levels encourage the growth of this algae and slime, which will thickly coat the plants and fixtures, Making the water highly toxic for fish.

How to lower pH in an Aquarium

Chemical solution

Possibly the most common way to lower the pH in aquariums is by using a bottle of chemical solution. Fritz and Kordon offer products with labels like "water softener" 'pH reducer'. "pH Lower" and so on.

CO2 Reactors

While not usually used specifically for acidity, if you use live plants, you really should be looking at using a CO2 reactor.

Water changes

If your aquarium pH is already high (greater than pH 7), combining your efforts to reduce pH with a water change is a good idea.

Symptoms of Low pH in an aquarium

  • Dirt build-up at the bottom of the tank.
  • Stressed fish.
  • Fish laying on the bottom of the fish tank, or hanging out at the surface.
  • Pale-looking fish.
  • Algae growth. As algae thrive in slightly acidic water, algae growth is often the first sign your fish tank has a low pH level.

Causes and Effects of Low pH in an Aquarium

Usually, the culprit behind low pH in an aquarium is poor maintenance. As fish waste and uneaten food collect in the aquarium, they break down and put off more nitrate (No-). Nitrate is acidic. So, the more it builds up in the water, the more it drives the pH down.

Low pH reduces your fish's ability to swim, eat, reproduce and grow everything it must do to survive. If your fish become stressed, they will seem sluggish, often sleeping more than usual.

How to raise pH in an Aquarium

  • Use reverse osmosis (RO) or deionized (DI) water to create the desired pH and buffering.
  • Use crushed coral or dolomite gravel for the substrate.
  • Decorate your aquarium with limestone or coral rock.
  • Fill a mesh media bag with crushed coral or dolomite gravel and place it in your filter.

How to monitor the pH in your aquarium

The first step in knowing whether or not the pH in your aquarium needs to be adjusted is getting an accurate reading.

We can easily buy monitor reading equipment on Amazon.

pH water test kits

pH reagents-based drip kit like APL'S pond testing is the classic way to test your pH. By adding water into a tube and adding the test reagents, you can watch as the water changes Color.

Match your water's Color to an included chart and you'll know with relative precision how acidic or basic your water is.

  • These kits are inexpensive.
  • Easy to use.
  • Offer a fair amount of accuracy.

Do Algae raise pH in aquariums?

In addition to carbon dioxide, algae influence the levels of nitrogen compounds in aquarium water. Algae absorb ammonia, nitrite, and nitrate. These chemicals are toxic. Additionally, they are typically associated with low pH, so algae raise pH by absorbing these compounds.

Do plants increase pH in Aquariums?

Plants can increase the pH level of water in the aquarium as they reduce carbon dioxide. Thus, the elimination of CO2 from the water can cause a rise in the pH level of water in the aquarium.

Does adding air to water change pH?

Increasing the oxygen concentration in your water will serve to drive down the carbon dioxide concentration. less carbon dioxide translates to a high pH. Therefore, you can increase the aeration in the tank to raise the pH.

Outgassing of carbon dioxide from water results in an increase in pH.