we just got a new tank, we put sand in with a little bit of water then filled it up. it was very cloudy at first but it seems as though most of it has settled down (its been about 48 hours) but it is still cloudy enough to make it hard to see through to the other side (the tank is 29 gallon, 29'' by 12''). we put in a light and when i look at it, it looks as though the rest of whatever is causing it to be cloudy is just floating around freely with no intention of settling. i do have a filter that hangs on the back and pours water back in that may be the cause of it? does anyone know typically how long it takes for the sand to completely settle or whether or not it is the sand that is making my tank cloudy. any advice is appreciated, thanks.