I went on vacation and the person watching my fish extremely over fed them. There was food everywhere. I changed 50 per cent of the water and pumped the gravel. What should I do next. One fish is already dying. The temperature was extremely low because they did not monitor it and then when I came back and turned of my AC the temperature shot up again from 74 to 79 degrees. How long should I wait to feed the fish? What should I do about the temperature?