I decided to change out my small gravel for sand in a 10 gallon that I'm going to use as a starter tank for cory cats. I took out the gravel early this morning and started rinsing through some sand and adding it to the tank. Then I got impatient and decided that the filter will clear the water and I added the rest of the sand. And now the water is cloudy...since this morning! I changed some water, added microbe lift an hour ago and still cloudy. Not that microbe lift would help that but I figured it couldn't hurt. I have a Whisper ex20 hob and I put a sponge filter in there a little while ago, still cloudy. Anyone have a problem like this? Should I just change out all the water? Had the tank running for about a month now cycling.