Recently I have notice that I need to add more and more water every day to my tank. It use to be I would have to add water maybe like 1/2 gallon every 3 days now im up to about 3/4-1 gallon a day anyone know why this would be. My water temp is 78 when the nightlight is on and 80.5 with the metal halide and the pc's. My room temp is 75 degrees if that helps at all