I have a used 125 gallon tank that I have had for a couple years. It has some scratches from the previous owner and I have trouble getting all the algea and such out of the scratches to make the glass look clean. I also noticed when I am doing water changes that as the water level lowers the glass out of the water has a really bad cloudy haze to it. I assume it is a lime build up. Is this normal or should I clean this off during water changes? Basically I am wanting to get my glass as clear as possible even though it has scratches. I know it has scratches so it won't be perfect, but it seems to have smudges and a slight haze to it on the inside.