a4b972ab_m_and_Freshwater_Fish_Problems__Problem
[Symptoms] Water temperature rises above 85 degrees. [Solution] Temperatures above 85 degrees can subject the fish to stress and even kill them unless they are fish which NEED that kind of heat (rare). Water will hold less oxygen at warmer temperatures than at colder temperatures. Therefore increasing the amount of aeration is often the best procedure when the aquarium becomes too warm. If the temperature goes above 90 degrees, ice cubes inside of plastic bags can be placed in the tank. Consider installing fans or a chiller. [Problem] 
Water too warm in summer
Aquarium and Freshwater Fish Problems
Problem