I was wondering most sites I've read have said to change the water with water 5-8 degres colder then the water in the tank..wouldn't this be accomplished by tossing 1 or 2 ice cubes into the tank? Since the ice cubes are made from purified drinking water, chlorine and metals aren't a problem..what do you guys think..also icepacks could work also could they not? Because, de-chlorinating a batch of water then cooling it then adding it in..more work then putting in a ice pack or an ice cube sounds logical to me..I'm probably just lazy