Hi. If there isn't a noticeable cloudiness, or milkyness to the water, i wouldn't worry about it too much. If you are looking at the tank through the long end than i can understand why the water may look a little cloudy. There are often tiny air bubbles in the water from the filter as well as small particulates that may reflect light giving the water a bit of a haziness. If the tank looks fine from the normal viewing angle it's probably not a big problem. Check your water stats to make sure nothing is amiss. If it's bothering you, do a series of small water changes over the course of a few days to see if that helps. In addition, you could try to feed less, and vacuum the gravel more if you so desire.