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What will happen to a saltwater marine fish kept in pure water?

Marine fish are known to adapt to a highly saline environment, thriving on the nutrients it provides. However, what will happen if they are kept in pure water? One might assume that removing the salt from a marine fish’s habitat would be detrimental to its health, and this assumption is correct.

The first thing that will happen to a marine fish kept in pure water is that it will start to lose its electrolytes. Without the essential minerals found within saltwater, a marine fish’s electrolyte balance will be thrown off, leading to dehydration and eventually, death. The fish will start to become lethargic and weak, and its body will begin to lose its natural color.

Another problem that arises with keeping marine fish in pure water is the absence of pH regulation. In the wild, the ocean’s pH is around 8.1, while freshwater has a pH of around 6 to 7. If a marine fish is kept in freshwater, its body’s pH level will become acidic, which can lead to multiple issues such as fatigue, damage to internal organs, and even death.

Another problem affecting marine fish kept in pure water is osmoregulation. Marine fish rely on the salt in seawater to maintain their internal salt and water balance. However, when these fish are in freshwater, they are unable to rid themselves of excess water, leading to bloating and eventually death.

If you want to keep marine fish in captivity, it is essential to provide them with an environment that is as close to their natural habitat as possible. This means providing them with the right level of salinity, pH, and other essential nutrients that they require to maintain optimal health. Failure to do so can have dire consequences for these creatures, who rely on the oceans to sustain themselves. So, before bringing home your next marine pet, make sure you understand how to provide them with the necessary environment they need to thrive.

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