pH and Nutrient Availability

Ed Wike
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pH: What is it and Why Does it Matter?

The pH scale ranges from 0 to 14. When pH is below 7.0 it is acidic. When pH is higher than 7.0 it is basic or alkaline. Most fish and aquarium plants prefer a stable alkaline level of 7.0-8.3. Water of pH 4.5 and below is considered toxic to fish.

Water and overfeeding can cause excess CO2 to build up in the aquarium. The CO2 (gas) dissolves into the water, causing acidity and lowering the pH. Low pH kills fish by leaching out calcium from their skeletons and drop

Ping the saturation point for the digestive enzymes that begin protein decay.

The most critical factor in determining the pH of a water is the presence and type of minerals in the water. Different minerals produce differing amounts of hydrogen ions when dissolved in water. While the EPA regulates the allowable limits of certain minerals in our water supply, water used for aquarium and pond keeping is unregulated. Minerals like iron, magnesium, and calcium in the water will also affect the pH.

Organic matter in the water can also affect pH. Algae will remove bicarbonate and carbonate ions causing a drop in pH. Most aquatic plants use bicarbonate as a source of carbon for photosynthesis. The bicarbonate is used to make carbohydrates by the plant cells in place of sugars. This means they will remove some of the bicarbonate.

Don’t Throw Your Nutrients in Jail

It is possible to use any old substrate in your aquarium, but we do not recommend it. A good substrate can improve the water parameters, helps get your aquarium off to a good start by providing essential nutrients, holds beneficial bacteria and offers a multitude of looks.

The most important thing to look for when considering a substrate is the pH level, around 6.5.

Some substrates are buffered with calcium carbonates, like crushed coral, that raise the pH.

Others are dead sea materials, which are usually neutral.

The majority of substrates don’t change the pH-level, but provide many other benefits.

When you rely solely on natural gravel, you are missing out on a wide variety of materials that are specifically designed for aquariums.

Manufacturers know what it takes to keep an aquarium alive and healthy over a long period of time.

They produce a substrate with a pH level close to 6.5, which has many benefits.

It’s never a bad idea to get a substrate that is specifically designed for aquatic life. They have the pH-level already determined and are otherwise veterinarian approved.

The water parameters in your aquarium will be a much safer bet in the long run if you choose a substrate that has been specifically designed for your needs and the needs of your fish.