ENVIRONMENTAL CONSIDERATIONS (cont)
Fish normally can tolerate a wide range of temperatures although thermal maximums and minimums exist that are species-specific. Zebrafish for example tolerate temperatures of 72 - 86 degrees F ( 22-30 degrees C ). Heat shock in zebrafish may occur if the temperature is maintained above 86 degrees F ( 30 degrees C ) and their metabolic rate may be lowered if the temperature is lower than 72 degrees F ( 22 degrees C ).
Any deliberate temperature changes made, such as increasing the temperature of a tank for breeding fish, should be gradual because rapid changes can be deleterious to fish health and will cause stress.