:;dogrun Hi , I have a 10 gallon tank with 4 mollies and 2 little tetras. I feed them tropical flakes, algae discs and blood worms. The ammonia reads 0.25, nitrites 0, nitrates 20 and temp is 64. No live plants. One of my mollies I think they sold to me is sick (staying at the bottom, lethargic, no eating). I just got him 3 days ago!. I want to increase the temp of the water to 80 degrees. Can I do that by adding hot water on my small daily changes?