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Understanding Water Hardness and How It Affects Fish

Understanding Water Hardness and How It Affects Fish

When keeping fish, most fish hobbyists want to ensure that their tank recreates the natural environment that their specific breeds of fish originate from. While using your fish’s specific needs as a guideline helps determine salinity, temperature, and pH, many people forget the importance of water hardness. If you want to give your fish the right environment to thrive in, read on to learn more about water hardness and how it affects fish.

What Is Water Hardness?

In terms of aquariums, water hardness refers to the level of minerals in the tank water. The most important minerals, calcium and magnesium, help aid your fish and other invertebrates in building their bones and exoskeletons. When determining how often you have to change your tank water, you should start by checking your water hardness along with the pH and ammonia levels. These measurements will allow you to get a better profile of your fish’s general health and well-being and tell you whether a partial water change is necessary.

Luckily, many test kits allow you to measure water hardness at home. Typically, this measurement is in degrees of general hardness known as GH. However, you may also see this measurement in parts per million (ppm). The conversion is 1℉GH per 17.848 ppm. Depending on your fish’s needs, you may also want to measure carbonate hardness (dKH) to determine the carbonates and bicarbonates in the water.

How Does It Affect My Fish?

The hardness levels in your tank can affect a fish’s skeleton or exoskeleton, but this goes beyond an issue of brittle bone structure. Without the right water hardness, you may stunt your fish’s growth, and their immune system can take a turn for the worse.

Good levels of calcium and magnesium serve to beat out toxic metals in the water, such as lead, chromium, and zinc, which allows your fish to absorb healthy minerals instead. It’s also important to note that the presence of calcium and magnesium in your water greatly affects the pH levels and can cause significant changes.

How Do I Control the Levels of Water Hardness in My Tank?

Lowering the water hardness levels in your tank is extremely easy as there are many water softeners on the market designed to treat tank water. However, when increasing the water hardness levels, you have a few methods to choose from. You can add crushed coral or limestone as well as limestone or coral décor to increase your GH levels.

As you make this change, be sure to pay attention to your pH levels. The higher the acidity of the water, the faster the limestone and coral will break down, thus affecting the overall water hardness. There are also water hardness supplements you can rely on.

Understanding water hardness and how it affects your fish will help you create the perfect environment for your fish to live long and healthy lives. Always consider the individual needs of your fish when increasing or decreasing water hardness.

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