Aquarium Salt

Doing your research on the fish you plan to keep is essential—not just for their diet or tank size, but also for understanding their salt tolerance. While salt is often associated with marine tanks, it can also play a role in freshwater aquariums. In fact, many freshwater fish benefit from a low level of salt in the water, typically around 1.001–1.002 specific gravity (SG). This small amount can help support a fish’s immune system and create a less hospitable environment for common parasites.

However, not all freshwater species tolerate salt. Some are especially sensitive and may experience stress or even die if salt is added to their environment. That’s why it’s important to research your fish species and understand which fish can tolerate salt and which cannot before making any changes to your water chemistry.

In freshwater disease treatment, aquarium salt is often used as a natural remedy. It can reduce stress, help with osmoregulation, and assist in recovery from infections and wounds. But be careful—aquarium salt is not the same as table salt. Table salt usually contains additives like iodine or anti-caking agents, which can be harmful or even toxic to fish.

Also, keep in mind that saltwater aquarium salt and freshwater aquarium salt are formulated differently. Salt for marine tanks contains specific minerals and trace elements meant to replicate ocean water, while freshwater salt is usually just pure sodium chloride without additives.

When used correctly, aquarium salt can be a helpful tool—just make sure it’s the right type, in the right amount, and safe for the fish you’re keeping.