Aquaria Information from



   Salt water fish have to actually drink the water to keep from dehydrating. About 5% of their body weight has to be taken in hourly to rid themselves of excess salt. The salt is excreted through specialized cells in the gills, kidney and skin. Why then is an accurate specific gravity so important? The higher the salinity (or salt in the water), the harder the body has to work to get rid of it. This puts more stress on the fish and opens up more avenues for problems. A specific gravity of 1.019 to 1.022 is considered a healthy range. 

   An effective method in controlling certain parasites is varying the salinity. For instance, Ich can be controlled without medication or copper by lowering the specific gravity to 1.017 and raising the temperature to 82o F. 

The higher temperature causes the life cycle to speed up, and the lower salinity makes the Ich cells actually explode. After about a week, you can slowly return conditions to normal. 

   Remember, don't make drastic changes to the water condition all at once. This must be done gradually over a 2 or 3 day period to avoid shocking the livestock in the aquarium. Evaporate loss should also be replaced on a regular basis with fresh water. Keep in mind that different fish respond to variables in different ways, and always exercise care when making any changes to their environment.


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